ample is the conceptual survey of electricity and magnetism described by Maloney et al. (2001).
Although it is certainly useful to know how students think about physical situations and concepts at the start and end of instruction, it is also important to monitor changes in these ideas during the course of instruction to address specific student needs and modify instruction accordingly. Incorporating formative assessment practices into ongoing instruction requires quality assessment materials that are closely connected to conceptual models of student understanding, together with effective ways of presenting, scoring, and interpreting the assessment results. Time and efficiency are obviously of central importance: if the feedback is not available when the next instructional decisions need to be made, then important opportunities will be lost. An excellent example of an effort to integrate assessment and instruction is the facets-based instruction and assessment work performed by Minstrell and his colleagues described above (Minstrell, 1992; Hunt and Minstrell, 1994; Levidow et al., 1991). The focus of the research effort has been on identifying facets (mental representations for interpreting physical situations) of student knowledge and understanding for various topics in physics. These facets are incorporated into Diagnoser, a relatively simple-to-use computer program designed to help teachers evaluate the quality and consistency of student reasoning in physical situations.
The Diagnoser program presents sets of carefully designed problems and records student responses and justifications as a means of identifying their understanding. When needed, the program provides instructional prescriptions that are designed to challenge the student’s thinking and address a possible conceptual misunderstanding. The course instructor is provided with information about the range of student understanding in the class and can then adjust lessons accordingly. Minstrell and Hunt (1990) have demonstrated that the facets approach can be successfully adopted by teachers and that it produces better outcomes than instruction that lacks integrated diagnostic assessment.
Teacher knowledge of physics is typically not a serious concern, since most physics teachers have undergraduate or ad-