An evaluative study of the experimental tasks of the Ethiopian grade 12 chemistry textbook considering developing “science process skills”

Abstract

This study evaluates the experimental tasks of the Ethiopian grade 12 chemistry textbook vis-à-vis coverage of the essential components of science process skills (SPSs) using content analysis. All the procedures in an experiment were analyzed using rubrics of the inquiry-based task analysis inventory (ITAI) instrument. This instrument was based on 10 indicators of SPSs (observing, measuring, inferring, communicating, classifying, predicting, controlling variables, stating hypothesis, interpreting data, and formulating models). The results indicated that the most frequent basic SPS was observing (39.33%), followed by measuring (18.67%) and communicating (18%) compared to the sum total of frequency occurrence of overall skills counted in all experimental procedures. The indicators of other components of the basic process skills are at low level. Almost all integrated skills are not reflected by the experimental tasks. Therefore, we can conclude that the SPS exercised by the experimental instructions is at low level. This study recommends that curriculum developers, textbook writers, and teachers shall revisit the experimental tasks to include SPSs at a reasonable balance.

Keywords:

• science process skills
• experimental tasks
• content analysis
• textbook

1. Background of the study

1.1. Research methodology

In the past, the rule of the game in chemistry instruction was based on a behaviorist model, but it is now gradually shifting toward the constructivist paradigm (Spencer, 1999). The constructivist educational philosophy asserts that understanding and knowledge of the world are constructed through students’ experiences and reflecting those experiences. They construct much of what they learn through interaction with targeted events. It requires learners to be active participants to develop their own skills and knowledge. Learning occurs only when the learner explores the truth/knowledge through experimentation and doing (Adom et al., 2016; Simsek & Kabapinar, 2010).

A constructivist approach could be used in learning chemistry to make the skill or knowledge acquired more meaningful (Abd Rauf et al., 2013). Students’ involvement in scientific processes is important for effective science education. This practice involves conducting practical scientific activities, producing and using scientific information and problem-solving (Safaah et al., 2017). Experimental tasks could guide such kinds of practices to be a character in a student self learning by inculcating science process skills (SPSs). Thus, SPSs are major components in science education.

The essence of science is not just about the content but also the process (Gunawan et al., 2019). Science is a process of discovery as well as the mastery of knowledge. SPSs are best exercised if they are included in laboratory tasks (Paterson, 2019). A limitation of the majority of contemporary laboratory tasks is the frequent use of expository instructions (colloquially referred to as “cookbook”), allowing for the inclusion of more students in a rotation system with a number of predetermined experiments for them to carry out (Agustian et al., 2022). The design of these tasks is very important since students have to follow them and they guide students to learn the necessary skills. A study recommends that to achieve a unified learning aim, research should determine the optimal ratio of outside-of-lab and inside-of-lab activities (Kelley, 2021). Here, it is clear that one of the students’ activities is interacting with the laboratory procedures both outside and inside the laboratory. Students should understand the laboratory procedures before actually practicing the activities. They also use these procedures after the actual practice in writing the laboratory report. Therefore, the inclusion of SPSs in experimental procedures improves the quality of instruction.

SPSs are a driving factor for scientific inquiry and are deployed by scientists for scaffolding knowledge and critical thinking to solve scientific problems (Yildirim et al., 2016). SPSs are recommended as a progressive approach and grouped as basic process skills (such as observing, classifying, communicating, measuring, predicting, and inferring) and integrated process skills (such as controlling variables, formulating hypotheses, defining operationally, and formulating models). The progressive approach of SPS means that achievement of SPS depends on grade level. In general, primary school students are expected to accomplish basic SPSs, whereas high school students are expected to attain both basic and integrated SPSs (Yildirim et al., 2016).

Paterson reported that a key component of teaching chemistry is practical work as it enables the students to practice and understand the essential aspects of knowledge, methods, processes, and uses of science. Moreover, practical activities exemplify scientific concepts, develop investigative and practical skills, and motivate students (Paterson, 2019). However, the potential of practical activities can limit the potential it has for promoting students to think like scientists. Experimental instructions should guide students in practicing the development of SPSs.

Most of the experimental instructions in the history of science education were sufficient in guiding a student to undergo qualitative and quantitative observation and measurement. Few experimental instructions in textbooks trigger students to predict the results, and none of them asked the students to design an experiment. Since most of the laboratory experimental instructions ask students to typically record the observational data, students do not require data manipulation, prediction, or hypothesizing based on the results of the investigation (Arnous & Ayoubi, 2018). The laboratory manuals and instructions missed higher levels of inquiry process skills, i.e., experimental instructions do not guide students in the hypothesizing, interpreting data, and formulating models (Arnous & Ayoubi, 2018).

The data collection instrument “inquiry based task analysis inventory (ITAI)” used in this article was developed by Yang et al. (2019). It was validated by four science education experts. The first expert developed school-based curriculum and devoted in promoting students’ understanding about scientific inquiry. The second expert is a specialist in science and scientific inquiry. The third expert teach inquiry course in one of the secondary schools in Beijing. The fourth expert is the lead author of the article (Yang & Liu, 2016). All the four experts possessed a deep understanding of scientific inquiry, which enables validating the reliability of the collected data. To maximize ITAI acceptability, these four raters discussed in groups about the rational, goals, expectations, and meaning of each item and rubric in their study; they used the instrument independently (Yang & Liu, 2016). They showed inter-rater reliability, discriminant validity, convergent validity, and Cronbach’s alpha reliability of the instrument. All these were checked and found in the accepted range.

The philosophy behind this research is pragmatism, which argues that scientific phenomena can be understood both subjectively and objectively (Lodico et al., 2010). The research approach used in this mixed methods research (QUAL–QUAN), which focuses on detailed understanding of a central problem and collects data based on words and numbers (Creswell, 2012). Numbers and texts are used in the result and discussion of this research to analyze the data.

2. Rational and objectives of the study

Nowadays, science and technology has grown exponentially. To equip this growth properly, science education plays a key role in the future of society. As a result, its quality had given great attention, especially in developing countries (Abd Rauf et al., 2013). Many researchers (e.g., Ergül et al., 2011; Sideri & Skoumios, 2021; Simsek & Kabapinar, 2010) reported that teaching SPSs improves the quality in learning science. Curriculum designers prioritize SPSs in the learning of science (Mohd Saat, 2004). This is due to the fact that scientific literacy is not only important for future scientists but also for society at large, as it can be used and applied in day-to-day life. Even though all learners could not become scientists, SPSs instill scientific attitudes that are favorable to all individuals. Since SPSs can be used in everyday life, they are very important for every individual (Safaah et al., 2017). Acquisition of SPSs provides an opportunity to learn independently (Abd Rauf et al., 2013).

Textbooks are one of the major sources that help students to acquire knowledge on the learning process. In addition, they serve as clear primary source of curricula for teachers when used as content-based science education, especially for concepts that are considered as central elements for knowledge (Yang et al., 2019). The nature of experimental instructions presented in students’ textbook can guide learners for investigation, inquiry, and find out scientific ideas by themselves (Tamir & Lunetta, 1981).Many researches have been done due to the irreplaceable advantages of textbooks as an instructional media in classroom (Abd Rauf et al., 2013; Antrakusuma et al., 2017; Sideri & Skoumios, 2021; Simsek & Kabapinar, 2010; Yang et al., 2019). However, only a few studies e. g. (Assefa; Fay et al., 2007; Tamir & Lunetta, 1981; Yılmaz Senem, 2013); focused on the analysis of science process skills in experimental instructions. Students’ engagement in science process skills is a key focus in high school chemistry education to develop students’ self-sufficiency and efficiency in carrying out scientific inquiry. Carefully designed experimental instructions create a chance to manipulate and practice experiments which in turn develop process skills (Paterson, 2019). Therefore this research aims to check the extent to which science process skills are reflected in experimental instructions of chemistry textbook.

It is common that in Ethiopian high schools, the same textbook is used to integrate the experimental activities (processes) and the concepts, principles, and generalization (products) (Engida, 2002). It is also common that teachers in Ethiopian schools use textbooks as the primary teaching aid in their teaching. The practical tasks presented in the textbook are very important to understand the teaching-learning process with respect to SPSs. There is evidence that suggests the fact that despite the premium placed on the teaching of science and technology in the Ethiopian educational policy, activities in science education guide students to rote memorization, which cannot support innovation and creativity (Belay et al., 2016). Experimental instructions in chemistry textbook should guide students to develop SPSs so that they can exploit their potential to be future scientists.

Although the significance of students’ involvement in SPSs has long been recognized (Sideri & Skoumios, 2021), there is little research evaluating these skills in school science textbooks. The peer-reviewed literature lacks enough research on content analysis of high school science textbooks for the inclusion of process skills. For instance, Sideri and Skoumios (2021) indicated in their study that unbalanced distribution of SPSs in science textbooks is common and recommended to deepen the investigation into secondary school science texts. The study also suggests that there is poor coverage of process skills in Greek science textbooks. Another study analyzed primary school textbooks for coverage of SPSs and indicated in their findings that observing is the most frequently employed skill, whereas using data and modeling is the least used (Önder et al., 2022). Önder and his associates recommended that future research is needed to determine the coverage of SPSs in secondary school science textbooks. Studies concluded that SPSs are only partially represented and briefly taught in primary school science textbooks (Sideri & Skoumios, 2021; Önder et al., 2022). It was examined that content analysis of scientific textbooks from Indonesia and Japan, including experimental instructions, claimed that basic science skills are given higher weightage than the integrated SPSs (Duruk et al., 2017). Hence, this study is needed to assess the status and determine the frequency of each SPSs reflected in the analyzed textbook.

Experimental activities play an important role in the acquisition of SPSs (Gunawan et al., 2019; Paterson, 2019). The current study will contribute to the development of more clear understanding of SPSs by focusing solely on experimental activities, as opposed to the majority of other studies that analyze the whole scientific textbooks. In addition, many researchers (Duruk et al., 2017; Safaah et al., 2017; Sideri & Skoumios, 2021) have repeatedly recommended future research and practice in a balanced inclusion of components of SPSs in textbooks. The literature also noted that there is a variation in textbooks in grade levels in SPSs (Sideri & Skoumios, 2021). These authors report in their study in primary schools that grade 6 science textbook is composed of higher components of process skills than the average compared to other grade levels. According to the study, the science textbooks of other grade levels in the school constitute lower components of SPSs than the average. So research on content analysis of experimental tasks of grade 12 chemistry textbook for SPSs is required to assess the inclusion of SPS skills to clarify the issue on this level.

The most commonly cited SPSs are observation, classification, measurement and using numbers, time and spatial relations, making inferences, predictions, communication, controlling variables, interpreting data, defining operationally, formulating hypotheses, formulating models, and experimentation (Mohd Saat, 2004; Simsek & Kabapinar, 2010). In this study, the frequency of 10 SPSs was analyzed based on the scoring rubrics of ITAI (Yang & Liu, 2016). The content analysis (sometimes called document analysis) method was used to conduct this study. Examining written resources on the research topic without engaging in observation or interview is a technique called document analysis that is used to learn more about the subject and make sense of it (Önder et al., 2022).

Graph 1: Counted process skills versus frequency of their percentages.

Thus, the general objective of this study is to investigate the extent of SPSs reflected in the experimental tasks of the Ethiopian grade 12 chemistry textbook.

The specific objectives of this study are as follows:

• To identify SPSs that are frequently emphasized in experimental tasks.

• To determine the status of experimental instructions in helping students to develop both basic and integrated SPSs in the Ethiopian grade 12 textbook.

2.1. Research questions

Chemistry education in Ethiopia is very much related to textbooks, which act as the main source of instructional message to students. Thus, there is a need to analyze chemistry text book to identify its appropriateness toward the development of SPSs. The present study focuses on checking the extent of inclusion of SPS in experimental instructions and therefore tried to answer the following research questions:

1. Which level of science process skill is most frequently presented in the Ethiopian grade 12 textbook?

2. What is the status of grade 12 chemistry textbook in incorporating experimental tasks that help to develop science process skills?

2.2. Research design

The purpose of the current study was to ascertain whether SPSs are covered and determine the status of the experimental instructions in terms of SPSs included in the activities found in the Ethiopian chemistry for grade 12 textbook. The research design used in this study is a content analysis, which is described as

A research technique for making replicable and valid inferences from texts (or other meaningful matter) to the context of their use (Krippendorff, 2009) p.18.

Content analysis is the use of an analytical process to interpret and produce inferences. Content analysis was chosen in order to assign meaning to experimental instructions employed in a student textbook to make inferences about their meaning with respect to SPSs. Content analysis is a well-known and widely used technique for assessing the content of school textbooks (Önder et al., 2022). This approach is in line with the objective of the current study as it enables analysis of the experimental instructions found in the analyzed textbook. This specific level (grade 12) was chosen because students are expected to exercise SPSs as it is the highest level in Ethiopian high school education.

Each experimental instruction was assessed to determine how often each of the 10 SPSs was reflected. According to the instrument used (Table 1), an activity was given a “YES” response if an indicator SPS was identified to be utilized, but a “NO” response if it was not. For instance, some of the indicators for observing are explore, observe, and investigate. The category “classify” was identified by indicators such as compares and classify. The other category “communicating” is related to presents, discusses, etc. Interpreting data could be identified by using an indicators such as associates, analyze and soon (Duruk et al., 2017).

Table 1. Outline of experimental activities in different units in grade 12 chemistry textbook

Unit	Title of experiment	Page
I) Solution	Distinction between homogeneous and heterogeneous mixtures	3
	Investigating properties of some mixture	4
	Investigation of heat of solution	13
	Investigating the solubility of NaCl	17
	Preparation of solutions of known concentrations	37
	Preparation of solution of lower concentration from standard stock solution	40
II) Acid–base equilibria	Acid–base color of litmus in water solution	68
	The buffer action of solutions	92
	Acid–base titrations	99
III) Introduction to chemical thermodynamics	Measuring the standard molar enthalpy of neutralization	142
IV) Electrochemistry	Electrical conductivity test	166
	Investigating electrolysis of sodium chloride solution	173
	Determination of cell potential of Daniell cell	195
V) Chemistry and industry	Studying chemical properties of some metals	236
VI) Polymers	Synthesis of nylon	277

The frequencies of the “YES” for each SPS were added when the analysis was complete and expressed in percentage compared to the total frequency. The sum of the frequencies of SPSs is found to be 149, and the percentage of frequency of each skill is compared to this total frequency (149). The reason for calculating the percentage of the indicators of each skill is to see the relative presence of components of SPSs.

2.3. Data source

The main focus of this study is to investigate whether experimental instructions help students to acquire the development of SPSs. The qualitative approach is used to count the different components of SPSs through content analysis. Content analysis is described as the manifest and latent content of a curricular material (such as a book) analyzed through classification, tabulation, and evaluation of its key components in order to ascertain its meaning and probable effect (Krippendorff, 2009).

In this study, the contents of the experimental tasks analyzed were part of the Ethiopian grade 12 chemistry textbook, which was first published in 2009. The textbook comprises six units, which have a total of 15 experiments with different numbers of experimental tasks (procedures). As can be seen in Table 1, the first unit consists of six experimental activities, which is the largest number compared to other units. The second and fourth units each have three experimental activities. The third, fourth, and fifth units each have contributed one experimental activity (Table 2).

Table 2. Scoring rubrics of ITAI

No.	Skills	Scoring rubrics
1	Observing	If students are required to or must perform observation, mark Yes; otherwise, mark No
2	Inferring	If students are required to or must infer, mark Yes; otherwise, mark No
3	Measuring	If students are required to or must measure the variables directly related to research questions, mark Yes; otherwise, mark No
4	Communicating	If students are required to or must communicate as part of this task, mark Yes; otherwise, mark No
5	Classifying	If students are required to or must perform classification that is rigorously defined in the inquiry process (e.g., biological classification), mark Yes; otherwise, mark No
6	Predicting	If students are required to or must predict, mark Yes; otherwise, mark No
7	Controlling variables	If students are required to or must control variables, mark Yes; otherwise, mark No
8	Formulating hypothesis	If students are required to or must formulate hypotheses and this task in fact belongs to inquiries that necessarily test hypotheses (e.g., experimental inquiry), mark Yes; otherwise, mark No
9	Interpreting data	If students are required to or must interpret data, mark Yes; otherwise, mark No
10	Formulating models	If students are required to or must formulate models, mark Yes; otherwise, mark No

Source: Yang and Liu (2016), p. 23

Procedures of each experiment were analyzed against SPSs. We tried to analyze the status of SPSs and find the most frequent SPSs that were designed to be acquired in practical activities. Each instruction in an experiment was evaluated against indicators of one or more SPSs. The analysis of the contents was based on the qualitative approach, which was adapted from a framework called “ITAI” for 10 indicators of SPSs (observing, inferring, classifying, communicating, measuring, predicting, controlling variable, formulating hypothesis, interpreting data, and formulating models) (Yang & Liu, 2016).

Intra-rater reliability is the consistency of measurement made by a single person, and it can also be improved by monitoring, training, and ongoing education (Nordquist et al., 2017). Since the rater of this study is a single individual with no previous experience in scoring such type of data, ongoing training and feedback from the supervisor were considered important to increase the rating ability and the consistency in collecting data. To increase the reliability of the data, a repeated scoring of the first unit for SPSs of the analyzed textbook at different times was done before collecting the data from all units of the textbook.

2.4. Data gathering instrument

The indicators of SPSs were taken into consideration when analyzing the experimental instructions in the study’s scope of chemistry textbook. The textbook was assessed using ITAI. When conducting analyses, descriptive analysis was used to take into account the texts for the indicators of SPSs. The instrument “ITAI” was developed to evaluate the content of school science textbooks in China (Yang & Liu, 2016). Experimental instructions in chemistry textbook are expected to create access for students to practice these skills. Even though more than 14 skills are presented in the ITAI, this study focused on 10 SPSs to gather evidence in evaluating the experimental instructions of the Ethiopian grade 12 chemistry textbook. Detailed scoring rubric and the corresponding skills are presented with minor modification in Table 2.

3. Results and discussion

The purpose of this study was to determine whether or not science process skill SPS s are present in Ethiopian secondary school chemistry textbooks (grades 12). Content analysis was done on the textual laboratory tasks to evaluate the frequency of occurrences of science process skill SPS s. In the analyzed textbook, a total of 15 experiments are found, each consisting of a different number of procedures/tasks. Each experimental procedure was analyzed against one or more science process skill SPS s. As it is seen in Table 3, a total frequency of 149 sience process skills through out the 15 experimental tasks. The following frequency of skills with their percentage and values are found.: These are “ observing” (39.33%) 59, “ measuring ” (18.67%) 28, “communicating ” (18%) 27, inferring (14.67%) 22, classifying (5.33%) 8, predicting (2.67%) 4, and interpreting data (0.07%) 1.

Table 3. The frequency of science process skill SPS s in different units of experimental instructions

No.	Skills	Frequency occurrence
Unit		1st	2nd	3rd	4th	5th	6th	Total	Percentage
1	Observing	19	11	1	14	7	7	59	39.33%
2	Inferring	6	5	1	4	3	3	22	14.67%
3	Measuring	15	5	2	4	2	2	28	18.67%
4	Communicating	9	4	1	9	2	2	27	18%
5	Classifying	1	1	0	5	0	1	8	5.33%
6	Predicting	1	0	0	2	1	0	4	2.67%
7	Controlling variables	0	0	0	0	0	0	0
8	Formulating hypothesis	0	0	0	0	0	0	0
9	Interpreting data	1	0	0	0	0	1	1	0.07%
10	Formulating models	0	0	0	0	0	0	0
	Total							149	100%

The result in this study indicates that the SPSs of observing, measuring, communicating, and inferring received higher emphasis in the experimental tasks. This result is in line with another study (Sideri & Skoumios, 2021; Önder et al., 2022), which showed that there is not a balanced distribution of SPS engagement in the school textbooks under investigation, as some skills were used more frequently and to a larger extent than others. It is also consistent with earlier study in Ethiopian chemistry textbooks, which concludes that majority of activities involve students in a skill of observing (Engida, 2002). The skill to observe is demonstrated most frequently in diverse circumstances and is regarded as a turning point or a point at which basic SPS and integrated SPS can be combined in a developmental sequence (Duruk et al., 2017).

Table 3 makes it clear that the ability to control variables (0%), formulating hypothesis (0%), and formulating models (0%) throughout any of the experiments are the significant omissions from the analyzed chemistry textbook. The ability to interpret data (0.07 %, 1), predicting (2.67%, 4), and the ability to classify (5.33%, 8) are the next three skills that are not adequately developed. This result is similar with the study (Önder et al., 2022) of textbooks in primary schools that report using data and modeling is found to be the least prevalent but observations is the most frequent skill (Chakraborty & Kidman, 2022). This limited inclusion or complete exclusion may harm students’ scientific literacy, cognitive development, academic successes, and growth in knowledge of the nature of science (Sideri & Skoumios, 2021).

The first objective of this study was to identify SPSs frequently emphasized in experimental instructions. As noted earlier, the total number of frequency of SPSs counted by using indicators was 149. To compare the frequency of each skill to the total number of process skills reflected in all laboratory instructions, the percent value was calculated for each skill. Table 3 indicates that the most frequently counted component of SPS is observing (39.33%), followed by measuring (18.67%), communicating (18%), classifying (5.33%), predicting (2.67%), and interpreting data (0.07%). As can be seen in Graph 1, this study hardly found indicators of higher level integrated SPSs, such as controlling variables, formulating hypotheses, and formulating models.

The second objective of this study is to determine the status of the Ethiopian grade 12 textbook experimental instructions in helping students to develop both basic and integrated SPSs. As shown in Table 2 or Graph 1, the result suggests that the most frequent component of SPS is observation, followed by measurement and communication. However, the frequency of basic process skills such as inferring, classifying, and predicting is low. In addition, as can be seen in the graph, except for a single occurrence (almost none) of interpreting data, the indicators of integrated skills are not reflected by the experimental instructions. Therefore, we can conclude that the SPS exercised by the experimental instructions is at a lower level. Some of the basic SPSs frequently reflected in grade 12 chemistry textbook experimental instructions are discussed further.

3.1. Observation

Yang and Liu described observation as the use of senses, such as eye, hand, and nose, to gather data about object or event (Yang & Liu, 2016). The two dimensions of observation are qualitative and quantitative. In qualitative observation, characteristics of a substance are noticed, such as its color, shape, and smell. On the other hand, quantitative observation is focused on numerical or material quantities (Duruk et al., 2017). This is the first and most frequent skill included in experimental procedures of Ethiopian grade 12 chemistry textbook. Some of the indicators of observation in experimental procedures include the use of the naked eye or hand lens, the mixture forms two layers, the reaction increases the temperature of the system, stirring will dissolve the solute, and note the color intensity used to gather qualitative observation. The use of scientific instruments such as thermometer, balance, burette, pipette, and rulers which could be used to quantitative observation, etc., also helps students develop skill of observation. The result of this study is in line with that of other students (Chakraborty & Kidman, 2022; Engida, 2002; Sideri & Skoumios, 2021; Önder et al., 2022), which reported that observation is the most frequent skill in other earlier studies.

3.2. Inferring

This refers to the use of gathered data from observation to draw logical conclusions (El-Sabagh, 2011). It is the act of using observations to draw a conclusion or a judgment based on facts from observation or when making observations is impossible (Duruk et al., 2017). For instance, students may observe that boiling water forms vapor and condenses to form water droplets, so one can conclude that the evaporation of water is a physical change. Indicators of this skill in grade 12 chemistry laboratory instructions are that students are instructed to arrive at conclusions based on the information they collected. To mention one example, learners are asked to record the final and initial temperatures and decide whether the reaction is exothermic or endothermic. This skill is the fourth (14.67%) frequently reflected in the analyzed textbook.

3.3. Measuring

The dimension of an object or event is estimated using standard or non-standard instruments, as in identifying length, volume, mass, pH, temperature, etc. (El-Sabagh, 2011; Yang & Liu, 2016). To list, a few indicators with respect to measuring in the Ethiopian grade 12 chemistry textbook are the use of thermometer to measure the temperature of the system, use pH meter to measure the pH of lemon juice, measure 10 ml volume of NaOH, etc. Measuring is the second most frequently occurring skill (18.67%) in the experimental tasks of the analyzed textbook. The result of this study is consistent with another study regarding measuring and other skills, which reported that observing, measuring, and communicating are most frequently found (Chakraborty & Kidman, 2022).

3.4. Communicating

Communication is the process of sharing information, emotions, thoughts, and experiences using scientific language (Duruk et al., 2017). Students may use words, actions, graphic, symbols, etc., gathered from observation to describe actions or events. Some of the communication indicators used in the Ethiopian grade 12 textbook experimental activities are discussion of observations with the classmates and teacher, writing a report, completing a table given, writing the balanced chemical equations using symbols and formulas, and presenting them to the whole class. Communicating is one of the most frequent skills reflected in the experimental tasks of the analyzed textbook, which is consistent with another study that report this skill is one of the most frequent skill (Chakraborty & Kidman, 2022; Sideri & Skoumios, 2021).

3.5. Classifying

Classifying refers to the use of observed properties to group objects into different classes (El-Sabagh, 2011). It is described as the organization of observed traits belonging to objects or facts in accordance with relationships. Classification is important because it acknowledges that any similarity in one regard may also encompass the similarity in others and group objects or facts to prevent them from being entirely lost or abstruse (Duruk et al., 2017). According to the results, the analyzed textbook (5.33%) reflects small number of indicators of this skill. Some of the indicators of classification in grade 12 chemistry textbook classify mixtures as homogeneous and heterogeneous, group substances (beer, milk, juice, etc.) as acidic or basic, group metals as very reactive, moderately reactive, and unreactive toward water, collect elements from the environment, and classify as metal and nonmetal.

3.6. Predicting

Based on previously available data, students provide the outcome of the future event. More accurate and rational guesses could be provided if detailed information is available (El-Sabagh, 2011). Predicting is stating a future outcome based on a pattern of evidence (Chakraborty & Kidman, 2022). Even though the value of frequency is small (2.67%), the evidences of indicators are obtained from the analyzed textbook. Some indicators of “predicting” in the analyzed textbook book are correlating the color intensity with concentration, guessing the product of the reaction, etc.

3.7. Interpreting data

Interpreting data is associated with analyzing data in a way that makes it simple to identify any patterns that might point to inferences or assumptions (Duruk et al., 2017). It was found that in the second unit of acid–base equilibria of the analyzed textbook, students are asked to determine if there is a relation between an equivalent point and an end point, which requires interpreting their data and relating it to theory. In this activity, students must use a graph or table to interpret data. Therefore, this is counted as an indicator of interpreting data in the textbook, and when this is converted to a percentage, it equals to 0.07% as indicated in Table 3. This result is in line with a research that claims that “using the data and modeling” is rare in the study’s textbook (Önder et al., 2022).

4. Conclusion, recommendation, and limitation

SPSs and the cognitive growth of students are positively related. Creating SPSs encourages students’ critical thinking, evaluation, inquiry, problem-solving, and creativity. Students’ SPSs might grow progressively over time when they are purposefully incorporated into a textbook (Önder et al., 2022). This study investigated to clarify whether the experimental tasks/procedures in grade 12 chemistry textbook covered SPSs. Therefore, the study was targeted toward the analysis of the experimental instructions using the ITAI instrument for the frequency of SPS.

The result of this study highlights experimental tasks in the Ethiopian grade 12 textbook that support the development of SPSs for only some basic process skills. The highest frequency of SPSs reflected is observing, followed by measuring and communicating. Except for the aforementioned skills, the indicators of other components of basic process skills are at low level. Furthermore, almost all integrated skills are not reflected by the experimental instructions. Thus, the integrated SPSs reflected by the experimental instructions are also at low level.

This and other similar studies provide important implications for the modification of the experimental tasks with respect to SPSs. The result of this study showed that better evidence was obtained from the textbook for incorporating basic SPSs. However, integrated SPSs are almost ignored by the experimental tasks. It is vital to establish a balanced setting for the components of SPSs. Therefore, the Ethiopian Ministry of Education should provide orientation to curriculum designers, textbook writers, and teachers to revisit their practices in terms of including improvements in incorporating the important integrated SPSs.

The present study is carried out as a partial fulfillment of a doctoral-level course entitled “Preparation and Evaluation of Curricular Materials.” This study is only limited to data collected from experimental tasks that are expected to be done in a conventional chemistry laboratory. The startup practical activities for classroom learning and the field projects are not included in counting indicators of the SPSs due to the informal nature of the activities, i.e., they are presented without clearly written objectives and procedures. In addition, no consideration is given to how the experimental activities are actually performed in the classroom. So more compressive future research may be done by collecting data from students after practicing the experimental tasks.

The other limitation of the study is that the research was relying on gathering data by the researcher himself only. Even though, with proper follow-up of the supervisor, the rater of this study has a proper understanding of the scoring rubrics of ITAI through repeated practices, the accuracy of this data may be susceptible to some degree of unpredicted error and rarely verified independently.

Disclosure statement

No potential conflict of interest was reported by the authors.