Teaching assistants' performance at identifying common introductory student difficulties revealed by the conceptual survey of electricity and magnetism

Nafis I Karim,Chandralekha Singh,Alexandru Maries

doi:10.1119/perc.2017.pr.047

Abstract

We discuss research involving the Conceptual Survey of Electricity and Magnetism (CSEM) to evaluate one aspect of the pedagogical content knowledge of teaching assistants (TAs): the knowledge of introductory students' alternate conceptions in electricity and magnetism as revealed by the CSEM. For each item on the CSEM, the TAs were asked to (1) identify the most common incorrect answer choice of introductory physics students and (2) predict the percentage of introductory students who would answer the question correctly in a post-test. Then, we used the CSEM post-test data from approximately 400 introductory physics students (provided in the original paper describing the CSEM) to assess the extent to which the TAs were able to identify the alternate conceptions of introductory students related to electricity and magnetism. In addition, we conducted think-aloud interviews with TAs who had at least two semester of teaching experience in recitations to explore their reasoning about this task. We find that the TAs struggled to think about the difficulty of the questions from introductory students' perspective and they often underestimated the difficulty of the questions. Moreover, the TAs often expected certain incorrect answer choices to be common among introductory students when in fact those answer choices were not common.

Highlights

The Conceptual Survey of Electricity and Magnetism (CSEM) is a conceptual multiple-choice survey [1] commonly used to assess student learning in introductory electricity and magnetism courses
Many teaching assistants (TAs) noted that the task of thinking from an introductory physics student’s point of view was challenging; some even confessed that they did not feel confident about their performance in identifying the most common incorrect answers
There are 32 questions on the CSEM, due to space constraints, we focus only on a few insightful items relevant to the research questions RQ1 and RQ2 discussed below: RQ1 Are there situations in which a significant fraction of TAs selects answer choices that very few introductory students select? What are some common examples of reasoning that TAs use to select those answer choices?

Summary

Introduction

The Conceptual Survey of Electricity and Magnetism (CSEM) is a conceptual multiple-choice survey [1] commonly used to assess student learning in introductory electricity and magnetism courses. Pedagogical content knowledge, or PCK as defined by Shulman [2], includes “Understanding of the conceptions and preconceptions that students bring with them to the learning of those most frequently taught topics and lessons.”. According to this definition, knowledge of students’ common alternate conceptions is one aspect of PCK [2]. The research presented here uses the CSEM to explore this aspect of the PCK of physics graduate Teaching Assistants (TAs) in the context of electricity and magnetism. We investigate the extent to which physics TAs are able to identify common alternate conceptions of introductory students on individual items on the CSEM. Knowledge of the common difficulties and of the types of reasoning used by introductory physics students can be helpful in designing pedagogical strategies to improve student learning [2,3,4,5,6]

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Conclusion