Abstract
Increasing availability of technologies, such as CD ROMs and the World Wide Web, in schools means that more teachers will have the potential to implement student-centred, inquiry-based approaches to learning. Assessing what each student knows in a broad subject area, such as science, is difficult. Assessing students' understanding in circumstances where each student may pursue different topics of study, where there is no way to predict in advance what those topics of study will be and where the possible topics of study include natural phenomena which are only beginning to be studied by professional scientists, is even more difficult. The authors recently faced such a challenge. To meet the challenge, the authors chose to assess student learning using an open-ended concept map activity combined with a rubric which extracts quantitative information about the quality of understanding from each map. This article describes the method the authors developed, including tests of reliability and validity.