How Do My Students Think: Diagnosing Student Thinking
Understanding misperceptions is key early step


Joan Lucariello, PhD, City University of New York

Students do not come to school as blank slates to be filled with instruction. Rather, they come to school with considerable knowledge, some correct and some not. Either way, that knowledge is based on intuition, every-day experience, as well as what they have been taught in other settings.

Teachers and researchers generally refer to preinstructional knowledge as preconceptions. Since a considerable amount of our knowledge is organized by subject matter (mathematics, science, etc.), so too are our preconceptions. Before beginning instruction on any new topic, teachers need to know their students’ preconceptions because learning, and therefore instruction itself, varies depending on whether students’ preconceptions agree with the concepts being taught or contradict those concepts.

When preconceptions are consistent with the concepts in the assigned curriculum, student preconceptions are called anchoring conceptions. Learning, in such cases, is much easier. It becomes a matter of conceptual growth, enrichment, or adding to student knowledge. More often, teachers find themselves teaching concepts that are difficult for their students to learn because students’ preconceptions are inconsistent with the concepts being taught. In these cases, preconceptions are termed alternative conceptions or misconceptions.

Description of some common alternative conceptions (misconceptions) in different domains.

There are several reasons that teachers need to figure out students’ preconceptions before they begin instruction on a new topic. First (as noted above), learning and teaching vary considerably, depending on whether the teacher is confronting alternative conceptions (misconceptions) or correct (anchoring) conceptions about the concepts or theories to be taught. Second, any pre-assessment of student academic skills and student knowledge may not accurately reflect actual pupil skill and knowledge. In addition, student learning and achievement can increase when teachers better understand their students’ thinking about a concept. Furthermore, when teachers listen to and comprehend student thinking, it can expand their understanding of the subject matter, change their beliefs on how to teach, modify their practices and contribute to their professional growth.

The first phase of instruction should be “diagnostic.” Teachers should employ diagnostic techniques not only to find out what students know or understand about a topic (“preconceptions”), but also to find out about other aspects of student thinking. These include student-learning processes, those things that are either hard or easy for students to grasp, and the errors that students commonly make (see Marks, 1990, for further discussion). The problem is that even when teachers are interested in diagnosing student ideas and responses, they often use inappropriate methods to do so (Morrison & Lederman, 2003). Therefore, recommended diagnostic teaching practices — “Dos” — are provided in this module.