Teaching assistants (TAs) are often responsible for grading in introductory physics courses at large research universities. Their grading practices can shape students' approaches to problem solving and learning. Physics education research recommends grading practices that encourage students to provide evidence of understanding via explication of the problem-solving process. However, TAs may not necessarily grade in a manner that encourages students to provide evidence of understanding in their solutions. Within the context of a semester-long TA professional development course, we investigated whether encouraging TAs to use a grading rubric that appropriately weights the problem-solving process and having them reflect upon the benefits of using such a rubric prompts TAs to require evidence of understanding in student solutions. We examined how the TAs graded realistic student solutions to introductory physics problems before they were provided a rubric, whether TAs used the rubric as intended, whether they were consistent in grading similar solutions, and how TAs' grading criteria changed after discussing the benefits of a well-designed rubric. We find that many TAs typically applied the rubric consistently when grading similar student solutions but did not require students to provide evidence of understanding. TAs' written responses, class discussions, and individual interviews suggest that the instructional activities involving the grading rubrics in this study were not sufficient to change their grading practices. Interviews and class discussions suggest that helping TAs value a rubric that appropriately weights the problem-solving process may be challenging partly due to the TAs past educational experiences and the departmental context.
Teaching assistants' performance at identifying common introductory student difficulties revealed by the conceptual survey of electricity and magnetism
Exploring Pedagogical Content Knowledge of Teaching Assistants Using the Test of Understanding Graphs in Kinematics
运动学图形理解测验（英语：Test of Understanding Graphs in Kinetics，缩写：TUG-K）是Beichner在1994年开发的一个多项选择测验，用来评估学生对运动学图形的理解。TUG-K上的许多项目都有很强的干扰项选择，这与学生在运动学图形方面的常见困难相对应。如果教师不了解物理导论学生的共同困难，并在教学设计中明确考虑到这些困难，那么教学就不可能是有效的。我们评估的教学内容的知识，一年级的物理研究生参加了教学助理（TA）培训课程的主题所涵盖的TUG-K。特别是，对于TUG-K上的每个项目，研究生被要求识别他们认为最常被物理学入门学生选择的错误答案，如果他们在相关概念的指导后不知道正确答案。我们使用的研究生数据和数据从Beichner的原始文件介绍物理学的学生，以评估相关的教学内容的知识（PCK）的研究生。我们发现，虽然研究生，平均而言，表现优于随机猜测，在确定介绍学生的困难上的TUG-K，他们没有确定许多常见的困难，介绍学生有图形的运动学，即使在传统的教学。此外，我们发现，研究生的能力，以确定的困难，介绍学生是依赖于上下文。
Physics teaching assistants' views of different types of introductory problems: Challenge of perceiving the instructional benefits of context-rich and multiple-choice problems
