Context-based learning and metacognitive prompts for enhancing scientific text comprehension

ABSTRACT

Context-based learning (CBL), promoting students' scientific text comprehension, and fostering metacognitive skills, plays an important role in science education. Our study involves CBL through comprehension and analysis of adapted scientific articles. We developed a module which integrates metacognitive prompts for guiding students to monitor their understanding and improve their scientific text comprehension. We investigated the effect of these metacognitive prompts on scientific text comprehension as part of CBL in chemistry. About 670 high school chemistry students were randomly divided into three groups exposed to high- and low-intensity CBL. One of the high-intensity groups was also exposed to metacognitive prompts. Research tools included pre- and post-questionnaires aimed at measuring students' conceptual chemistry understanding and metacognitive knowledge in the context of reading strategies, before and after exposure to the CBL. Chemistry understanding was reflected by students' ability to identify the main subject of the adapted article and by explaining concepts both textually and visually. We found that high-intensity CBL combined with metacognitive prompts improved students' chemistry understanding of the adapted scientific articles and the ability to regulate their learning. Our study establishes that reading context-based adapted scientific articles advances students' conceptual chemistry understanding. These gains are strongly amplified by domain-specific metacognitive prompts.

KEYWORDS:

• Context-based learning
• scientific reading
• metacognition
• chemistry understanding

Introduction

Students should engage in practicing science to promote their scientific literacy (Holbrook & Rannikmae, 2007; Krajcik & Sutherland, 2010). Scientific literacy relates, among other things, to the ability to read and understand scientific texts (Fang & Wei, 2010; Yarden, 2009). Norris and Phillips (2003) claim that the ability to read research articles is a form of scientific literacy required for practicing science. Thus, emphasising scientific reading is essential in science education. This type of reading includes not only information absorption, but also an active approach while reading, such as analysing and interpretation of data and processes. However, a recent view of scientific literacy, based on the qualifications required for life-long skills of the twenty-first century, emphasises the need to enhance students’ thinking skills (Zohar & Dori, 2003) and to promote their metacognitive skills (Avargil, Lavi, & Dori, 2018) as part of the scientific literacy framework (Choi, Lee, Shin, Kim, & Krajcik, 2011; Yore & Treagust, 2006).

The context-based science learning approach reflects this view. Bybee (2015) provides a definition for scientific literacy that emphasises its connection to the context in which science is taught and learned. Giving context to science occurs when life situations involve science and technology, when one can apply scientific knowledge to the personal, social, and global problems they encounter as citizens, and when students can confront socio-scientific issues (NAP report: Beatty & Schweingruber, 2017); it is based on real-world problems with an emphasis on interdisciplinary connections, where applications of science provide starting points for developing scientific ideas (Bennett, Lubben, & Hogarth, 2007; Schwartz 2006). Therefore, context-based learning engages students in learning that demands activating their thinking and metacognitive skills, motivates students to learn, and encourages them to be scientifically-literate (Bennett & Holman, 2002). Students need to be able to interpret new complex scientific information, monitor their own previous and new knowledge, and decide if or when additional information is needed to solve a problem (Choi et al., 2011).

In chemistry education, teaching and learning should be based on subjects that are relevant to students’ lives and represent authentic relevant issues (Gilbert & Treagust, 2009). Following the approach that context-based science and metacognition might enhance students’ conceptual understanding and thinking strategies, we developed a context-based chemistry module. The module, titled All is Chemistry: Adapted Scientific Articles, engages students in practicing chemistry through reading context-based adapted scientific articles (adapted scientific articles in short) and answering complex questions based on these articles, thereby promoting conceptual understanding of chemistry.

Herscovitz, Kaberman, Saar, and Dori (2012) clarify that adapted scientific articles are based on primary sources: scientific articles, written by scientists for scientists or domain experts, allowing for communication among scientists. The primary scientific article usually contains evidence to support the conclusions in the method and results sections, and has a very structured format that includes an abstract, introduction, methods, results, and discussion sections. Similarly, the adapted scientific article of primary source has a structured format and includes evidence to support conclusions. However, to make the content more accessible to high school students, science educators, and often scientists, adapt the text of the original article and sometimes do not keep the same structure as the primary scientific article. Usually, the adapted scientific article is shorter than the primary article, containing mainly facts and graph or table, raises a problem but provides a reduced amount of evidence.

The module integrates adapted scientific articles and metacognitive prompts into context-based learning in chemistry. The articles chosen for this module are context-based, as they involve aspects from more than one scientific domain. They discuss societal, industrial, and ethical aspects and relate to topics that include applications of technological and social aspects, people’s activities, and life within a community or society (Bulte, Westbroek, de Jong, & Pilot, 2006). Through reading an adapted text, students develop an understanding of the meaning of a certain chemical phenomenon in a specific context. Our assumption is that this engagement helps to enhance the students’ chemical understanding.

The context in this module is associated with two models of context-based learning presented by Gilbert: ‘Model 2: Context as reciprocity between concepts and applications’ (Gilbert, 2006, p. 967) and ‘Model 4: Context as the social circumstances’ (Gilbert, 2006, pp. 969–970).

In Model 2, the application of concepts further deepens the meaning for students and helps them to structure broader chemical knowledge related to the concepts. In this model, students can relate their new understanding to their previous one, and depending on the teacher, they can apply the concepts in their own language while relating to their own environment. However, social aspects and participation in a community of practice are missing in this model, while in Model 4, the social context and the culture of a society are at the centre. Debates using the chemical concepts are in place, and deeper understanding is created through a community of practice that involves both the students and the teacher. In Model 4, the knowledge a teacher possesses both in the content aspect and the pedagogical aspect is key factor in his/her teaching.

Attending to the characteristics of the activities, which students carried out in their classes and based on Gilbert’s models, we found a mix of Models 2 and 4. Based on teachers’ self-reports and our own observations, in some situations, the implementation of the activities was carried out by the students in a way that was similar to Model 2, while in other situations, it was similar to Model 4. Since this mix was distributed equally among the three groups, we did not use it as a variable in our analysis.

For example, learning about structure and bonding through an adapted scientific article about food colourings was associated with Model 2. Students found new insights through this application and learned about new substances with respect to health issues associated with Tartrazine. A different adapted article, Diamonds Forever, was more closely aligned with Model 4. Through this article, students gain new understanding of the structure of a crystal by learning about the production of human-made diamonds from a loved-one’s cremated ashes. The context of this article also prompted discussions with societal flavour and implications, and the debates between the students and their teacher, while using the chemical concepts, were inevitable.

Metacognitive prompts integrated in the module guide the students to monitor their ability to identify the main subject of the article, understand the main concepts, and answer complex questions both textually and visually. Developing these skills is based on the four chemistry understanding levels, which together foster conceptual understanding of chemistry. The four levels are the macroscopic (macro), microscopic (micro or sub-microscopic level), symbol, and process (Dori & Sasson, 2008; Gilbert & Treagust, 2009; Taber, 2013).

In this study, we investigated the effect of different levels of exposure to context-based adapted scientific articles and metacognitive prompts on students’ ability to read, analyse and develop conceptual chemistry understanding. We first define context-based learning, with respect to reading adapted scientific articles, and then elaborate on metacognitive prompts for supporting scientific reading.

Theoretical background

Scientific literacy – reading scientific articles

Scientific literacy can be defined broadly, as it relates to different goals of science education. An important pillar of scientific literacy is the ability to read and understand scientific texts (Norris & Phillips, 2015). This relates to ‘Vision II’ of scientific literacy, explained by Roberts (2007) as ‘situations with a scientific component students are likely to encounter as citizens’ (p.730). In his review of the historical development of the term, he explains that the definition is broad and has many components, one of which is the ability to read texts with scientific vocabulary, terms, and meaning. Thus, reading scientific texts is an important component of scientific literacy.

Reading adapted scientific articles is a vital part of communicating scientific knowledge, and the nature of science, to high school students (Pearson, Moje, & Greenleaf, 2010; Phillips & Norris, 2009). Such reading promotes the establishment of an independent life-long learner, who can read, analyse and understand new texts independently (Yarden, 2009). The ability to comprehend scientific texts helps develop literacy among students, eventually making them scientifically-literate citizens (Wellington & Osborne, 2001; Yore et al., 2004). The abilities associated with deep understanding of scientific texts include understanding the meaning and significance of the main subject, connecting new scientific knowledge with previous knowledge, and the ability to understand new concepts. This ability leads to an understanding of reported science-related issues that affect citizens’ lives, their ability to understand scientific discoveries, and communicate science-related issues to peers (DeBoer, 2000; Millar & Osborne, 1998).

Fang (2005) claims that:

To become scientifically literate, students must ultimately learn to cope with the specialized language of science. For example, students must be able to read and comprehend texts where scientific knowledge and ideas are typically presented in school . … Scientific texts require students to understand not only the linguistic text but also the scientific material. (p. 345).

Reading science is part of the professional life of scientists, and is central to their success (Michalsky, 2013; Phillips & Norris, 2009). Thus, teaching science through reading is part of conveying to students the way scientists work. Reading scientific articles while learning science is essential for students, since when they graduate from high school and become active contributors to civil society, it is important for them to be able to read and understand texts such as media reports on scientific, environmental, and health issues (Fang, 2005; Kouba & Champagne, 1998; Norris & Phillips, 2003). Many students, however, have difficulties reading and understanding science content (Carnine & Carnine, 2004; Peacock & Weedon, 2002). Fang (2005) specified the complex structure of a scientific text and the components that differentiate it from other texts – including technical language, abstract meaning, language density, and a specific hierarchical structure – as the main reasons for these difficulties in understanding. The nature and characteristics of scientific texts are challenging for students due in part to their perceived distance from the students’ daily lives.

Context-based science and reading scientific texts

Reading adapted scientific articles as part of a context-based approach helps students develop an understanding of scientific concepts, and how these concepts are connected to real-world problems (Dori, Tal, & Tsaushu, 2003; Hand et al., 2003; Herscovitz et al., 2012). In Finland, for example, scores on PISA Scientific Literacy Assessment, which assesses scientific reading, went up since their science curriculum started emphasising context-based approaches that include examples of health education, and life sciences in physics and chemistry (Lavonen & Laaksonen, 2009). Conceptual understanding of scientific articles accounts for both textual and visual comprehension. It includes looking for meaning, connecting newly acquired concepts to prior knowledge, and making visual representations of knowledge, concepts or ideas, which may help to guide the thoughts in the learner’s mind (Dori & Sasson, 2008; Malik & Zaman, 2012; Wandersee, 1988).

Chemical literacy and reading context-based chemistry texts

Part of the goal of teaching All is Chemistry is facilitating students’ general scientific literacy. Chemical literacy has unique features within the broad definition of scientific literacy (Gilbert & Treagust, 2009). Shwartz, Ben-Zvi, and Hofstein (2005) explored these features and explained that beyond general scientific literacy, chemical content-knowledge can also explain phenomena in other areas. A chemically-literate person should be able, for example, to understand chemistry in context and use it to explain everyday phenomena, understand chemistry in daily life, and discuss chemistry-related issues in a social debate (Bennett & Holman, 2002; Sevian & Talanquer, 2014). Moreover, chemical literacy includes the characteristics of chemistry, which are at the core of a conceptual chemistry understanding. This kind of understanding, and the ability to explain scientific and daily phenomena, is based on one’s grasp of the four chemistry understanding levels – the macro, micro, symbol, and process levels. Indeed, the chemistry understanding levels, and the connection between them, are at the heart of chemistry reasoning.

However, few students’ reasoning skills include the different understanding levels (Chittleborough & Treagust, 2007; Dori & Hameiri, 2003; Johnstone, 1993; Tsaparlis & Sevian, 2013); because identifying the chemistry levels and their connections is challenging for students, thus they often need assistance in making these connections (Taber, 2013). Such help can come from reading context-based adapted scientific articles in chemistry, which is expected to enable students to better explain chemical scientific ideas, using the four chemistry understanding levels.

Reading strategies for better conceptual understanding of science

Reading strategies in general, and reading strategies for scientific text in particular, are documented as raising students’ scientific literacy and their reading comprehension. ‘Good readers’ use reading strategies more frequently (Ferguson-Hessler & de Jong, 1990; Yore, Craig, & Maguire, 1998).

Explicit instruction on how to develop and use reading strategies can benefit learners. Most of the research that supports the explicit instruction of reading strategies for better comprehension and conceptual understanding of science was done in elementary or middle school settings (Fang & Wei, 2010), and used cognitive strategies for reading. For example, Fang and Wei (2010) compared an experimental group of 6th grade students with a comparison group. The experimental group was exposed to reading strategies such as predicting before continuing reading, questioning, using concept maps, note taking, paraphrasing, and other cognitive strategies. Each strategy was discussed, and later used, in the experimental group. The students in the experimental group outperformed their peers in both their science conceptual understanding and their ability to read scientific texts.

The current study focuses on explicit instruction for developing reading strategies based on metacognitive abilities for reading (Wang, Chen, Fang, & Chou, 2014; Yore & Treagust, 2006). Researchers argue that metacognition is a central feature in life-long learning in general, science education in particular, and that metacognitive engagement is key in developing deeper conceptual understanding of scientific ideas (e.g. Choi et al., 2011; Georghiades, 2004; Koch, 2001; Wang et al., 2014).

Metacognitive prompts for supporting scientific reading

Metacognition may enhance students’ ability to use scientific concepts in context (Georghiades, 2004), improve their science reading comprehension (Norris & Phillips, 2012), and enhance their ability to monitor their own reading (Wang et al., 2014). Achieving this goal can be supported through metacognitive guidance and training, such as prompts for how and when to use reading strategies (Koch, 2001; Sjöström & Eilks, 2018).

Metacognition includes conscious selection of learning strategies and matching these to the task’s demands (Flavell, 1979; Schraw, Crippen, & Hartley, 2006). Many researchers agree that metacognition consists of knowledge and regulation of one’s own cognition. Knowledge of cognition refers to what we know about our own cognition and includes three sub-components, one of which is procedural knowledge. Procedural knowledge is the knowledge a person possesses about strategies, such as note-taking, summarising main ideas, skimming, etc. (Schraw et al., 2006). Effective reading strategies can further support students, and advance them from the phase of just understanding the words of the article, to the phase of building conceptual understanding of the scientific concepts (Hand et al., 2003; Yore, Bisanz, & Hand, 2003). With respect to reading, Wandersee (1988) found that most college students were not familiar with reading strategies, and the most popular strategy they used was reading and re-reading the text.

Regulation of cognition refers to knowledge about the way of planning, monitoring, and evaluation of cognitive processes (Schraw & Moshman, 1995; Schraw et al., 2006). In our study, we evaluate the monitoring sub-component.

Monitoring includes the abilities of self-testing in order to monitor and control learning, monitor cognitive activities, and to judge whether one’s understanding is sufficient (Schraw et al., 2006; Thomas, Anderson, & Nashon, 2008). Herscovitz et al. (2012) exposed high school chemistry students to a metacognitive tool that supported monitoring of the kinds of questions students asked after reading a scientific text. After using the metacognitive tool, students were able to pose more complex questions, indicating that they had developed sophisticated understanding of concepts and processes.

Norris and Phillips (2012) have also conducted research on scientific reading and metacognition. The authors expound upon the term reading metacognition, which includes the regulation of thinking during and after reading. Reading-metacognition relates to explicitly posing metacognitive questions, such as

How well do I understand the last passage? Should I reread it? In what way does it relate to the first two paragraphs? Perhaps I should look up that unusual word in the dictionary. How does this article fit with the one I read last week? (p. 38).

They investigated students’ metacognitive judgments about the difficulty of the text and how the reading affected their earlier beliefs. Students systematically overestimated the degree of their certainty in their report. They confused evidence statements as conclusions, and dramatically underestimated the demands of the text and the cognitive difficulty they had experienced with the interpretative tasks. Thus, students’ performance on the reading tasks had a very weak correlation with their perceived difficulty of reading these texts.

Explicit exposure to metacognition, metacognitive tools and strategies support student achievement (Thomas & McRobbie, 2001). Given the importance of monitoring in metacognition, there is a need to increase the level of metacognitive monitoring in actual classroom practice (Nietfeld, Cao, & Osborne, 2006).

In light of the importance of explicit monitoring in metacognition, one way to support students’ ability to monitor their cognitive processes is to use metacognitive prompts. Zhang, Hsu, Wang, and Ho (2015) showed that metacognitive prompts helped students monitor and evaluate their learning, and promoted scientific understanding while engaging in scientific inquiry. Sandi-Urena, Cooper, and Stevens (2011) showed that metacognitive prompts aimed at fostering planning, monitoring, and evaluating, improved college students’ problem-solving skills. Chiu and Linn (2012) investigated how students monitored their own progress while using prompts to mediate their understanding of chemical phenomena. Asking students to explain their reasoning guided them to monitor their understanding, identify gaps in their knowledge, and refine their ideas. Indeed, these prompts enhanced students’ reasoning and guided them to monitor their understanding while identifying gaps in their knowledge.

We are not aware of studies that have investigated the effect of reading context-based adapted scientific articles together with metacognitive prompts on students’ conceptual understanding of scientific texts. This gap in the literature exists specifically in studies on high school students with domain-specific metacognitive support. Through this research, in response to Kramarski and Mevarech’s (2003) suggestion of distinguishing between general- and domain-specific metacognitive knowledge, we sought to promote domain-specific metacognitive knowledge in chemistry. Our study aims to examine students’ chemistry understanding and metacognitive procedural knowledge through reading context-based adapted chemistry articles and using metacognitive prompts for monitoring learning.

Specifically, we applied the following three chemistry learning methods: (1) high-intensity context-based learning with metacognitive prompts, (2) high-intensity context-based learning without metacognition prompts, and (3) low-intensity context-based learning. This research structure was applied to test our hypothesis that reading more context-based adapted chemistry articles (high-intensity context-based learning) will have a more significant effect on students than reading fewer articles (low-intensity context-based learning). An additional objective was to test the hypothesis that introducing students to metacognitive prompts while reading context-based adapted chemistry articles promotes chemistry understanding and procedural knowledge.

To this end, we asked the following research questions:

1. Will differences be found in (1) students’ chemistry understanding as reflected by the ability to identify the main subject of the article, and express chemistry understanding textually and visually; and (2) students’ procedural knowledge in the context of reading strategies?

2. Will there be a relationship between the two skills investigated in the first research question (students’ chemistry understanding and its expression) and students’ procedural knowledge?

Method

Participants

The research participants included 428 students in the 11th (80%) and 12th (20%) grades from 24 high schools in Israel, who chose to major in chemistry. They participated in a three-unit chemistry matriculation examination at the end of the school year. The participants come from high schools in a variety of geographical regions. No differences were found between the three groups with respect to academic level, type of school (urban or periphery), class (11th or 12th), or gender. Participants were divided into three groups based on their teachers’ willingness to participate in the research and devote class hours to teaching science through context-based adapted scientific articles: (1) High-intensity Context-Based Learning with Metacognition scaffolding (HCBL + MC); (2) High-intensity Context-Based Learning (HCBL); and (3) Low-intensity Context-Based Learning (LCBL).

Training programme and procedure

The three research groups were given the same number of chemistry classes per week and were taught the same contents required for passing the Israeli three-unit chemistry matriculation examination. The three research groups responded to 20-minute pre- and post Reading strategies questionnaires followed by 40-minute pre- and post Adapted scientific article questionnaires, before and after being exposed to the context-based learning. The Adapted scientific article pre-questionnaire related to the first adapted scientific article, and the post-questionnaire related to the fifth and last article.

The students were divided into three research groups, based on different intensity of their context-based chemistry learning. There were two high-intensity research groups: HCBL + MC and HCBL. Both groups were tasked with reading and analysing five unseen adapted scientific articles in chemistry. The third research group was low-intensity context-based learning (LCBL), and students in this group read only the first and last articles. The LCBL group read only two articles and responded to the assignments that followed similar to those that HCBL + MC and HCBL groups performed; while the HCBL + MC and HCBL groups responded to all the assignments after reading the five articles. These articles, taken from scientific sources, were translated from English to Hebrew and later to Arabic, and adapted to match the knowledge-level of high school chemistry students. The content included in the articles was part of the chemistry curriculum. These 500 to 600-word articles, which focused on chemistry topics with increasing levels of difficulty, had the following titles: (1) ‘Walking on the Ceiling with Geckos’ – inter-molecular forces; (2) ‘Diamonds Forever’ – material structure; (3) ‘The Baghdad Vessel Mystery’ – redox reactions; (4) ‘Strongest but Gentle Acid’ – acid–base reactions and material structure; and (5) ‘Oceans Are Becoming More Acidic’ – acids and bases. The adapted context-based scientific articles, as well as the questionnaires that followed, enabled teachers and students to have productive interactions with one another and the text, exploring additional aspects of chemical concepts in relation to the context, as suggested by Gilbert (2006). For example, the concepts embedded in article ‘Walking on the Ceiling with Geckos’ elicited discussion on applications in the industry, and the concepts embedded in the material structure article, ‘Diamonds Forever,’ elicited contextual discussions about ethical and social–scientific issues.

Both high-intensity groups read the same five articles, but differed in that the HCBL + MC group was also exposed to metacognitive prompts. This differentiation enabled us to assess the effect of using metacognitive prompts while reading. These metacognitive prompts helped the students monitor their understanding while performing reading tasks that accompanied the adapted scientific articles. As noted, the low-intensity context-based learning (LCBL) students read only the first and last articles, and had no exposure to the metacognitive prompts. This enabled us to assess the effect of high vs. low-level intensity of context-based learning.

The metacognitive prompts (see Appendix 1), developed by Kaberman and Dori (2009), guided the students how to monitor their understanding for improving meaningful comprehension of adapted scientific articles. It served as scaffolding for constructing teachers’ and students’ chemistry knowledge and understanding. The prompts included explanations about (1) the meaning of the main subject and concepts of the article, and (2) the four levels of chemistry understanding. The explanations were accompanied by questions to monitor students’ understanding.

The chemistry teachers in the study participated in a one-week professional development programme in a prominent science and technology institute of higher education in preparation for implementing the module. During the programme, the teachers were exposed to context-based adapted scientific articles and the metacognitive prompts, and were directed to apply context-based learning methods in their classes.

Assessment tools and criteria

We employed two assessment tools: (1) an Adapted scientific article questionnaire, which included open-ended questions, regarding the expression of chemistry understanding textually and visually, and aimed at assessing students’ chemistry understanding; and (2) a Reading strategies questionnaire, adapted from Wandersee’s (1988) questionnaire – Ways students read texts – which aimed at identifying students’ procedural knowledge through the use of a variety of reading or self-questioning strategies while reading.

The Adapted scientific article questionnaire included open-ended questions that accompanied the adapted article, aimed at assessing students’ chemistry understanding in the three aspects presented below, along with examples and criteria for scoring each aspect, based on previous studies (Dori, Dangur, Avargil, & Peskin, 2014; Dori & Herscovitz, 1999, 2005).

Aspect 1: Identifying the main subject and concepts of the article – Students were asked to identify the main subject of the adapted scientific article, describe it in three to four sentences, choose one main concept from the adapted scientific article, and explain it.

Scores were given based on three criteria: (1) Identifying the main subject, for which possible scores were 0 – lack of identification; 1 – partial, low level identification; and 2 – complete, high level identification; (2) Identifying key concepts that were included in the adapted scientific article, for which possible scores were 0 – lack of identification; 1 – identification of one concept; 2 – identification of two concepts; (3) Applying chemistry understanding levels (macro, micro, symbol, and process) in the student’s explanation of the concepts, for which possible scores were 0 – lack of chemistry understanding; 1 – one level of chemistry understanding; 2 – two levels of chemistry understanding; and 3 – three or four levels of chemistry understanding.

Scores for these three criteria were summed, and ranged between zero and seven. The following is an example of a student’s response that received the highest score on the adapted scientific article ‘Oceans are becoming more acidic,’ with the scoring criteria and interpretation indicated in brackets:

Decrease in the pH of the Earth’s oceans. As a result of fuels combustion and CO₂ emissions, there is a decrease in the pH [identifying the first main concept: pH] of water ocean [identifying the main subject] which may reach 7.3 in 2300 [process level]. This decrease would badly affect the animals in the oceans, particularly those whose skeletal bodies are built of calcite, CaCO₃, [process and symbol levels] which reacts with acid [macroscopic, identifying the second main concept: ecological systems].

The student fully identified the main subject and two key concepts, and expressed chemistry understanding in the macro, symbol and process levels, with emphasis on to the concept of ecological systems.

Aspect 2: Expressing chemistry understanding textually – Students were asked to express textually what they had understood. For example, the following paragraph appeared in the adapted scientific article ‘Oceans are becoming more acidic,’ and the student had to explain to what chemical processes the text refers.

Increasing the use of fossil fuel expands the amount of carbon dioxide emitted into the air as a result of the combustion process. Most of the carbon dioxide is probably absorbed by the sea water, and when it dissolves in water it creates carbonic acid that causes a decrease in pH.

Scores were given based on two criteria: (1) Quality of the answer, for which possible scores were 0 – incorrect; 1 – partially correct; and 2 – fully correct; (2) Number of chemistry understanding levels (see Aspect 1). Scores for these two criteria were summed, and could range between zero and five. Following is an example of a student’s response that received the highest score:

The process of burning in which CO₂(g) is emitted [process and symbol levels]; CO₂(g) + H₂O(l) → H₂CO₃(aq) weak acid [microscopic and symbol levels]; The process of acid–base reaction and the releasing of H₃O⁺(aq) ions [process and symbol levels] [recognizing the three chemistry processes].

Aspect 3: Expressing chemistry understanding visually – The students were asked to draw a visual explanation or representation of the chemical phenomena they read about in the adapted scientific text. For example, in ‘Oceans are becoming more acidic’, the student was asked to draw a schematic illustration of the buffer effect and explain each element in the picture. Scores were given based on four criteria: (1) Verbal explanation accompanying the drawing, for which possible scores were 0 – lack of drawing; 1 – only drawing; 2 – drawing accompanied by textual explanations; (2) The relevance of the drawing to the subject of the article, for which possible scores were 0 – lack of relevance; 1 – the drawing is relevant to the subject of the article, but reflects low chemistry understanding of the concept; 2 – the drawing is relevant to the subject of the article and reflects chemistry understanding of the concept; (3) The number of items in the drawing, for which possible scores were 0 – two items or less in the drawing; 1 – three or four items; 2 – more than four items; (4) Number of chemistry understanding levels (see Aspect 1).

Scores for these four criteria were summed, and could range between zero and nine. Following is an example of a student’s drawing that received the highest score, in ‘Oceans are becoming more acidic’.

Figure 1 presents a student’s drawing that is relevant to the main subject and concepts of the article and expresses chemistry understanding regarding the reasons for the increase in acidity, receiving a score of two for relevance. It is accompanied by an adequate textual explanation, receiving a score of two for textual explanation. It includes six items: constant pH, calcite, neutralisation, OH⁻(aq), H₃O⁺ (aq) and phrasing the process, receiving a score of two for number of items. Finally, these items represent three levels of chemistry understanding, at the macro, symbol and process, receiving a score of three for number of chemistry understanding levels.

Figure 1. An example of student’s visual representation.

The second assessment tool was the Reading strategies questionnaire, which was used to determine students’ procedural knowledge according to their own declaration of using various strategies and procedures while reading. In what follows, we present these strategies and procedures, and our criteria for their scoring. (1) Reading strategies, for which scores could be 0 – no method; 1 – reviewing (e.g. reading aloud); 2 – search for meaning (e.g. looking for key sentences); 3 – building contextual understanding (e.g. linking to prior knowledge). (2) Diversifying and adjusting reading methods, for which scores could be 0 – unwillingness to learn; 1 – willingness to learn; 2 – willingness to learn, as well as diversifying and adjusting reading methods. (3) Using visual means, for which scores could be 0 – no use; 1 – highlighting; 2 – using diagrams or tables. (4) Self-questioning, for which scores could be 0 – no questions; 1 – questioning for searching the topic of the article (e.g. What is the subject of the article?); 2 – questioning for giving meaning to the information in the article (e.g. What is the subject of the article and do I understand it?); 3 – questioning for providing valuable information (e.g. Why do I need to know this information?); 4 – questioning for linking to prior knowledge (e.g. How is this related to what we have studied at school?).

In the Reading strategies questionnaire, a student could score a maximum of 11 points, and based on this score, a level of procedural knowledge was assigned to each student as follows. A student who scored two or below was classified as demonstrating almost No Procedural Knowledge (NPK). A level of Low Procedural Knowledge (LPK) was given to students who scored between three and five. Intermediate Procedural Knowledge (IPK) corresponded to a scores between six and eight, and students who scored between nine and eleven were classified as having High Procedural Knowledge (HPK).

Findings

In order to investigate students’ context-based learning in chemistry through scientific text comprehension, and answer our research questions, we analysed students’ chemistry understanding and procedural knowledge. In what follows, we present findings referring to: (1) students’ chemistry understanding; (2) students’ procedural knowledge; and (3) the relationship between students’ procedural knowledge and students’ chemistry understanding. Our independent variables were reading context based scientific texts and using metacognitive prompts. Our dependent variables were chemistry understanding, as reflected by identifying the main subject of the article, expressing chemistry understanding levels textually and visually, and students’ procedural knowledge.

Students’ chemistry understanding

Students’ chemistry understanding was assessed through the following cognitive skills: (1) identifying the main subject and concepts in adapted scientific articles; (2) textual explanation; and (3) visual representation. We present findings separately for each cognitive skill.

Identifying the main subject and concepts

A Two-Way ANOVA with Repeated Measures was conducted to investigate the differences in a student’s ability to identify the main subject and concepts from the pre- to the post-questionnaires (relating the first and last adapted articles, respectively). In this analysis, the between-subjects independent variable was group and the within-subjects independent variable was time of measuring. The dependent variable was the score received for identifying the main subject and concepts in the articles.

Findings revealed a significant interaction between group and time, F(2,425) = 4.95, p < .01. Simple main effect tests with Bonferroni adjustment, separately for each group, indicated that although participants’ scores increased in all three groups, this increase was higher among participants in the HCBL + MC group (p < .001), followed by participants from HCBL group (p < .005) and LCBL (p < .01), as Figure 2 shows.

Figure 2. Students’ scores in the assignment of identifying the main subject and concepts.

Textual explanation

The scores for chemistry understanding were determined by the quality of answers and the number of chemistry understanding levels that students used in their answers. A Two-Way ANOVA with Repeated Measures was conducted to investigate the difference in the scores given for textual explanation from the pre- questionnaire to the post-questionnaire. In this analysis too, the between-subjects independent variable was group and the within-subjects independent variable was time of measuring. The dependent variable was the textual explanation score. Findings revealed a significant interaction between group and time, F(2,398) = 6.73, p < .005. Simple main effect tests with Bonferroni adjustment, done separately for each group, indicated that while participants’ scores in the HCBL + MC group increased, participants’ scores in both HCBL and LCBL groups decreased, as shown in Figure 3.

Figure 3. Students’ scores in chemical understanding as expressed by their textual explanations.

Moreover, the percentage of students in the HCBL + MC group who incorporated two chemistry understanding levels in their textual explanations increased from the pre- questionnaire to the post-questionnaire. While the overall HCBL students’ textual explanation scores decreased, their use of the micro and symbol levels increased. The LCBL group students mostly used the macroscopic level in their post-questionnaire textual explanations.

Visual representation

Score for expressing chemistry understanding visually was determined by the quality of drawing and the number of chemistry understanding levels that were expressed in the drawings. A Two-Way ANOVA with Repeated Measures was conducted to investigate the difference in the score for visual representation from the pre- to the post-questionnaires. As before, the between-subjects independent variable was group and the within-subjects independent variable was time of measuring. The dependent variable was the visual representation score. Findings revealed a significant interaction between group and time, F(2,393) = 28.4, p < .0001. Simple main effect tests with Bonferroni adjustment, separately for each group, indicated that while participants’ scores in the HCBL + MC group increased, participants’ scores in the LCBL group decreased and participants’ scores in the HCBL group remained the same, as can be seen in Figure 4.

Figure 4. Students’ scores in chemical understanding via visual representations.

Further analysis revealed that the percentage of students who used several levels of chemistry understanding in their visual responses was similar to the finding related to their textual explanations. The ability of HCBL + MC students to incorporate more chemistry understanding levels in their drawings increased. In this group, there was a decline from the pre- to the post-questionnaire in the use of only the macro level and two chemistry understanding levels. Conversely, an increase was evident in the use of the micro and symbol levels and three or more chemistry understanding levels. Here, as in the textual explanation, we also found that the percentage of HCBL students who used the micro and symbol levels in their answers increased, compared with the LCBL group students, who mostly continued using the macroscopic level.

Students’ procedural knowledge

We refer to four metacognitive levels of a student’s procedural knowledge: NPK – Almost no procedural knowledge, LPK – Low procedural knowledge, IPK – Intermediate procedural knowledge, and HPK – High procedural knowledge. One of these four levels was assigned to each student based on a combined score for her or his use of the following procedural knowledge while reading: (1) reading strategies, (2) diversifying and adjusting reading methods, (3) using visual means, and (4) self-questioning.

Table 1 presents the relationship between the procedural knowledge levels and the overall chemistry understanding score, showing a direct relationship between the two.

Table 1. The relationship between procedural knowledge and chemistry understanding in reading adapted articles.

Procedural metacognitive knowledge	N	Overall chemistry understanding score
HPK	47	4.0
IPK	177	3.2
LPK	75	3.0
NPK	105	1.8

Chi-square tests of independence were performed to examine the relationships between the research group and students’ procedural knowledge level, separately for each time of measuring (pre/post). The relationship between these variables was not significant at the pre-questionnaire χ²(6) = 1.03, p > .05, but was significant at the post-questionnaire, χ²(6) = 22.8, p < .001. This means that while for the pre-questionnaire there was no difference between students’ procedural knowledge level by research group, at the post-questionnaire, students’ level of procedural knowledge was dependent on the group they belonged to.

As Figure 5 shows, based on the Reading strategies post-questionnaire, the percentage of HPK students was the highest among the HCBL + MC group (17.1%), and the lowest among the LCBL group (4.6%). The percentage of NPK students was the lowest among the HCBL + MC group (19.9%) and the highest among the LCBL group (35.1%). Since the students in all three groups had a similar starting point, these findings indicate the effect of the context-based article reading on students’ level of procedural knowledge. The percentage of HPK among HCBL group students decreases slightly to 9.7% but it was still double than that of the LCBL group (4.6%).

Figure 5. Procedural knowledge level while reading.

Relationship between students’ chemical understanding and procedural knowledge

A One-Way ANOVA was conducted in order to investigate the difference in the overall chemistry understanding score, based on the student’s procedural knowledge level (NPK, LPK, IPK, or HPK). Findings revealed a significant effect of the procedural knowledge level, F(3,403) = 3.63, p < .05. Post-hoc analyses using the Scheffé Post-hoc criterion for significance indicated that the average chemistry understanding score was the highest among the HPK students, followed by IPK or LPK students, and the lowest for NPK.

Conclusions and discussion

Reading adapted scientific articles is an essential part of science teaching and for preparing an autonomous life-long learner (Bybee, 2015; Roberts, 2007). Scientific texts differ from other texts in their goals, structure, and cognitive demands (Carnine & Carnine, 2004; Fang, 2005; Peacock & Weedon, 2002). Our research investigated chemistry major students who were exposed to context-based adapted scientific articles. To this end, we developed the All is Chemistry: Adapted Scientific Articles module, in which chemistry concepts were presented with their everyday applications. This module is associated with two models of context-based learning presented by Gilbert (2006), whose Model 2 pertains to context as interchange between concepts and their applications, and to Model 4 pertaining to the social aspects of context. According to these two models, students relate to the concept being introduced with a new understanding, achieved through relevant and societal context. For example, in the article ‘Oceans are becoming more acidic’, students learn about acids and bases through air pollution that affects oceans’ pH.

The context-based adapted scientific articles require also the application of at least a subset of the four chemistry understanding levels – symbolic, macroscopic, microscopic, and process (Dori et al., 2014; Dori & Hameiri, 2003; Dori & Sasson, 2008). These articles were presented to students at two intensity levels: high and low. Two groups were exposed to high intensity context-based learning through reading five adapted context-based scientific articles. One of these groups was exposed to metacognitive prompts to monitor their answers to questions after reading the article, while the other group did not get the support. A third group was exposed to low intensity context-based learning through reading only two adapted scientific articles without the metacognitive support.

The findings show that students who were exposed to high-intensity context-based learning with metacognitive prompts (HCBL + MC) identified the main subject and concepts of the adapted scientific article in the post-questionnaire better than the rest of the students, as the increase in students’ scores from the pre- to the post-questionnaires was significantly higher in this group than the other two groups. The ability of students who were exposed to high-intensity context-based learning (HCBL) to identify the main subject and concepts in an adapted scientific article also increased. This increase was significantly higher than the increase in students’ scores who were exposed to low-intensity context based learning (LCBL).

These findings support two important claims of the study. The first is that in order to engage students in meaningful reading of science that results in conceptual chemistry understanding, a context-based approach is effective and therefore should be favourably considered (Bennett & Holman, 2002). The fact that students have difficulties in reading scientific text (Carnine & Carnine, 2004; Peacock & Weedon, 2002) but need this ability as part of scientific literacy skills (Fang, 2005; Kouba & Champagne, 1998; Norris & Phillips, 2003) can be supported by placing scientific reading in context that relates to daily life (Beatty & Schweingruber, 2017).

The second claim, which our findings support, is that metacognitive prompts for monitoring students’ reading and their answers to the questions after reading could promote the understanding of scientific texts as these prompts increase students’ ability to identify the main subject and concepts in the article. According to Hand et al. (2003), reading science is not just recognising words or locating information in the text. Rather, it entails a constructive process of making meaning. The authors claim that ‘scientific knowledge has an essential dependence on texts, and the route to scientific knowledgeability is through gaining access to those texts’ (p. 612). Gaining access entails the ability to understand the text by first understanding its main goal, then realising the main subject and then the main concepts and how they relate to each other.

Students’ chemistry understanding was determined by the quality of their answers and the number of chemistry understanding levels they used in both their textual and visual explanations. This method of assessment is aligned with the NAP report recommendation (Beatty & Schweingruber, 2017) to ‘examine how students use science and engineering practices in the context of crosscutting concepts and disciplinary core ideas’ (p. 18).

Students’ chemistry understanding scores in the HCBL + MC group increased from the pre-questionnaire to the post-questionnaire. HCBL + MC students also used more chemistry understanding levels in their answers compared to the other two research groups. This benefit can be attributed to the fact that during the learning process, students in the HCBL + MC group monitored their answers based on chemistry understanding levels using domain-specific metacognitive prompts (Herscovitz et al., 2012; Kramarski & Mevarech, 2003). Although the articles’ level of difficulty increased, the ability of the HCBL + MC students to provide high-quality answers and incorporate a variety of chemistry understanding levels in their answers increased.

A benefit of the context-based approach was observed even without the metacognitive prompts, albeit to a lesser extent. HCBL students demonstrated three trends from the pre- to the post-questionnaires: (1) their chemical understanding scores through textual explanation decreased, (2) their chemical understanding scores through visual representation remain the same, and (3) their use of two or more levels of chemistry understanding in their answers increased. A factor that can explain the decrease in trend (1) is the increasing level of article difficulty. Comparing these findings with LCBL group students, their scores decreased from the pre- to the post-questionnaires in all aspects and they used mostly the macroscopic level in their answers. This comparison supports our claim that the advantage of context-based approach is mainly when it is implemented in a high-intensity setting. This is in line with Shwartz et al. (2005).

Using different chemistry understanding levels in explanation and argumentation is an indication of better conceptual chemistry understanding. Indeed, HCBL + MC group students increased the use of the micro and symbol levels and the use of three or more chemistry understanding levels from the pre- to the post-questionnaire. We also found that HCBL students used in the post-questionnaire the micro or symbol levels to a larger extent than in the pre-questionnaire.

This finding indicates correlation between levels of metacognitive support and conceptual chemistry understanding. More generally, we find that students’ chemical understanding, expressed through both textual explanations and visual representations, can be deepened via the use of domain-specific metacognitive prompts.

Prompting students to monitor their answers increased their procedural knowledge, so metacognitive prompts did not just help regulate students’ cognition, but also advanced their knowledge of cognition in the aspect of procedural knowledge. Wang et al. (2014) showed that higher metacognition levels correlated with better science reading comprehension. Indeed, we showed that explicit exposure to metacognition is related to students’ conceptual chemistry understanding and can improve science reading, specifically in context-based learning.

Limitation, contribution and further research

The current study demonstrates the contribution of context-based learning with metacognitive prompts for promoting chemistry literacy. However, the sample in this study were students who chose to major in chemistry. In order to generalise the findings to a wider population, we should examine the recurrence of the findings in other countries and among students who study chemistry as a compulsory subject. However, since we had diverse student population, e.g. by residence (urban vs. rural) and geographical (central vs. periphery), the heterogeneity might prove that our findings may be valid for another diverse population.

Teachers and their students have a positive attitude toward incorporating reading scientific articles while learning science, but teachers report lack of knowledge and experience of how to teach science through reading (Gillespie & Rasinski, 1989; Yore, 1991). Our study shows that placing reading in context can help students learn science through reading and specifically advance conceptual chemistry understanding. These gains are strongly amplified when students are provided with domain-specific metacognitive prompts.

Students are more engaged in learning when a context-based learning approach is applied (Bennett, Gräsel, Parchmann, & Waddington, 2005; Watanabe, Nunes, Mebane, Scalise, & Claesgens, 2007). Thus, our findings support that context-based learning environment is an effective vehicle for promoting students’ chemical literacy and that the four chemistry understanding levels can contribute to both teaching and learning while serving as metacognitive prompts. Students need support in reading science (Fang, 2005; Phillips & Norris, 2009), but when students graduate from the K-12 educational system and choose to pursue a scientific career, they will need to cope with scientific texts in science textbooks and journals. Research on how a context-based approach and metacognitive guidance can lead to reading complex scientific texts will advance our knowledge regarding learning science through reading. Hence, studies on the effect of context-based learning and metacognition on learning science through reading should intensify. Specifically, the contribution of context-based learning to scientific reading can be further investigated by comparing two groups of students tasked with the same amount of reading, where one group gets context-based scientific articles and the other group reads about the same scientific concepts from non-context based scientific texts.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Yehudit Judy Dori http://orcid.org/0000-0001-7775-5872

Shirly Avargil http://orcid.org/0000-0003-4515-126X

Zehavit Kohen http://orcid.org/0000-0003-2084-4780

Liora Saar http://orcid.org/0000-0003-0734-7253

Appendix 1: The metacognitive prompts.

Understanding concepts and main subject:

A recommended method for understanding an article is first reading it superficiality in order to identify the general ideas that are covered by the article, and then reading deeply each paragraph and identify the main subject and concepts. The following guidelines are recommended: (1) Pay attention to the title of the article; (2) Highlight key concepts. Features of a key concept include: (1) the concept appears multiple times in the article; (2) the content of the article or parts of it are not comprehensible without understanding the concept; (3) Make a note of what is the area in which the article discusses; (4) According to your initial impression, list general ideas, of which the article deals with; and (5) Read each paragraph or two and write the idea that is presented in them, or mark a sentence that represents their main idea. Collect the sentences you have noted and list the main issues that the article deals with, in their sequence. Use these notes to identify the main subject and concepts.

Self-monitoring: (1) check whether the chosen concepts are aligned with the features of key concepts. Justify your decision; (2) check whether the main subject you have noted, is suitable to your initial impression of the article. If necessary, change the subject you have chosen.

Knowledge and chemistry understanding:

Understanding of a chemical phenomenon can be represented in four levels of chemistry understanding: (1) Macroscopic level – relates to aspects of the phenomenon that can be sensed (colour, smell); (2) Microscopic level – relates to particles by which the material is made – atoms, molecules, ions; (3) Symbol – gives a symbolic representation to the phenomenon (formula, graphs, drawing); (4) Process – relates to aspects of occurrence of process / chemical reaction and sometimes combines the other levels of chemistry understanding.

The ability to switch and link the various levels of chemistry understanding is important, as it is an indication to high level of chemistry understanding.

Self-monitoring: (1) read the answer to question 2 [expressing chemistry understanding textually] and check whether you referred to at least two levels of chemistry understanding. If necessary, expand your answer; (2) use the following table and specify where you used the various levels of chemistry understanding in your response to question 2.