In this study, we evaluate the impact of rehearsing teaching skills in a mixed-reality classroom simulator on graduate teaching assistants’ (GTAs) instructional practices as well as undergraduate student learning outcomes. The simulator training is intended to provide GTAs opportunities to deliberately practice essential pedagogical skills that support active learning, specifically in the context of the combined tutorial and laboratory sections of an algebra-based introductory physics sequence. Over three semesters, GTAs participated in different numbers of simulator rehearsal sessions: no simulator training, one session, and four sessions. We conducted 109 classroom observations for 23 GTAs, using a modified version of the Laboratory Observation Protocol for Undergraduate STEM (LOPUS); we also documented the frequencies of questioning-related skills (e.g., cold calling) implemented by the GTAs. Undergraduate student learning outcomes were measured by pre- and posttests of the Force Concept Inventory (FCI) and Conceptual Survey of Electricity and Magnetism (CSEM). To classify and characterize GTAs’ instructional practices, we conducted a hierarchical cluster analysis and found three instructional styles: the small-group facilitator, the whole-class facilitator, and the waiter. The results suggest that four-session simulator training throughout a semester supported GTAs (i) to shift away from the style of the waiter toward the whole-class facilitator, and (ii) to implement posing questions and cold calling techniques. While new GTAs were found to have more interactive behaviors than experienced GTAs in the semester with no simulator training, we found that four-session simulator training supported both new and experienced GTAs to use more interactive instructional styles and to implement questioning-related skills more frequently. Although the results demonstrate the effectiveness of simulator training, our analysis also indicates areas for improvement. GTAs tended to shift away from the style of the small-group facilitator toward the whole-class facilitator when they participated in four-session training, and the weekly implementations of questioning-related skills decreased over the course of a semester despite an increased total implementation. In addition, student learning outcomes in different semesters (with different numbers of simulator rehearsal sessions) did not show a statistically significant difference. However, GTAs’ instructional styles were correlated with student performance on FCI posttest with a small effect size when controlling for FCI pretest scores and lecture instructors; no correlation was found between GTAs’ instructional style and student performance on the CSEM posttest. We conclude with a discussion of factors that may have led to the success of the simulator training as well as strategies to further enhance the effectiveness of the simulator training.

中文翻译：

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评估课堂模拟器培训对研究生助教教学实践和本科生学习的影响

在这项研究中，我们评估了在混合现实课堂模拟器中排练教学技能对研究生助教 (GTA) 教学实践以及本科生学习成果的影响。模拟器培训旨在为 GTA 提供有意识地练习支持主动学习的基本教学技能的机会，特别是在基于代数的物理入门序列的教程和实验室部分相结合的背景下。在三个学期中，GTA 参加了不同数量的模拟器排练：无模拟器培训、一节和四节。我们使用修改版的本科 STEM (LOPUS) 实验室观察协议对 23 个 GTA 进行了 109 次课堂观察；我们还记录了 GTA 实施的与提问相关的技能（例如，电话咨询）的频率。本科生的学习成果是通过力概念量表 (FCI) 和电和磁力概念调查 (CSEM) 的前后测来衡量的。为了对 GTA 的教学实践进行分类和表征，我们进行了层次聚类分析，发现了三种教学风格：小组辅导员、全班辅导员和服务员。结果表明，整个学期的四节模拟器培训支持 GTA (i) 从服务员的风格转变为全班辅导员，以及 (ii) 实施提出问题和冷呼叫技术。虽然发现新 GTA 在没有模拟器培训的学期中比有经验的 GTA 具有更多的互动行为，但我们发现四节模拟器培训支持新老 GTA 使用更多互动教学风格并更频繁地实施与提问相关的技能. 虽然结果证明了模拟器培训的有效性，但我们的分析也指出了需要改进的地方。GTA 在参加四节课的培训时倾向于从小组辅导员的风格转变为全班辅导员的风格，尽管总体实施增加，但与提问相关技能的每周实施在一个学期中有所下降. 此外，学生在不同学期（模拟排练次数不同）的学习成果没有显示出统计学上的显着差异。然而，当控制 FCI 前测分数和讲师时，GTA 的教学风格与学生在 FCI 后测中的表现相关，影响大小较小；没有发现 GTA 的教学风格与学生在 CSEM 后测中的表现之间存在相关性。最后，我们讨论了可能导致模拟器培训成功的因素以及进一步提高模拟器培训有效性的策略。GTA 的教学风格与学生在 FCI 后测中的表现相关，当控制 FCI 前测分数和讲师时，效应量很小；没有发现 GTA 的教学风格与学生在 CSEM 后测中的表现之间存在相关性。最后，我们讨论了可能导致模拟器培训成功的因素以及进一步提高模拟器培训有效性的策略。GTA 的教学风格与学生在 FCI 后测中的表现相关，当控制 FCI 前测分数和讲师时，效应量很小；没有发现 GTA 的教学风格与学生在 CSEM 后测中的表现之间存在相关性。最后，我们讨论了可能导致模拟器培训成功的因素以及进一步提高模拟器培训有效性的策略。