Teaching Organic Chemistry Through Gesture, Action, and Mental Imagery

Many undergraduate chemistry students struggle to understand the concept of stereoisomers, molecules that have the same molecular formula and sequence of bonded atoms but are different in how their atoms are oriented in space. Our goal in this study is to improve stereoisomer instruction by getting participants actively involved in the lesson. Using a pretest-posttest design, we asked participants to enact molecule rotation in three ways: (1) by gesturing the molecules’ movements; (2) by imagining the molecules’ movements; or (3) by physically moving models of the molecules. Because sex differences have been found in students’ understanding of chemistry (Moss-Racusin et al., 2018), we also examined how male and female students responded to each of our 3 types of instruction. Undergraduate students took a pretest on stereoisomers, were randomly assigned to one of the 3 types of instruction in stereoisomers, and then took a posttest. We found that, controlling for pretest performance, participants made robust improvements after instruction, and that all 3 types of training were effective for both females and males. We end with recommendations for stereoisomer instruction based on our findings.

众多本科生在理解立体异构体概念上存在困难，立体异构体是指具有相同分子式和键合原子序列的分子，但其原子在空间中的取向不同。本研究的目标是通过使参与者积极参与课程，以提升立体异构体的教学。采用前测-后测设计，我们要求参与者以三种方式实施分子旋转：（1）通过手势模拟分子的运动；（2）通过想象分子的运动；（3）通过物理移动分子的模型。鉴于性别差异已被发现影响学生对化学的理解（Moss-Racusin 等人，2018年），我们还探讨了男性和女性学生对我们三种教学方法的反应。本科生在立体异构体测试中接受前测，随机分配到立体异构体教学的三种类型之一，然后进行后测。我们发现，在控制前测表现的情况下，参与者经过教学后取得了显著的进步，且三种类型的培训对女性和男性都同样有效。基于我们的发现，我们提出了关于立体异构体教学的建议。