Undergraduate science students spend a substantial amount of time working in their laboratory groups, and instructors want to make evidence-based decisions on how to best set up these groups. Despite several studies on group composition, the evidence appears to be quite context-specific, and very little has been published about lab groups. Further, many studies focus solely on conceptual learning; however, the lab is an important venue for also supporting non-content outcomes such as confidence, process skills, team skills, and attitudes. Thus, in our introductory course on molecules, cells, and physiology we were interested in the impact of group composition, on a spread of student outcomes. Students were either placed into groups by the instructor, or self-selected into groups. To assess the impact of group composition on student outcome, we collected pre/post data from >500 students over 2 semesters. Our measures assess conceptual knowledge, confidence in lab skills, attitudes toward group learning, lab grades, gender, year of study, and (via open-ended questions) student perspectives. Using a multiple regression approach, we established models that predict student outcomes based on their individual attributes and on their lab group attributes. Surprisingly, the hetero/homogeneity of the initial group, and whether the groups were student- or instructor-selected, did not affect student outcomes in these models. Further MANCOVA analysis demonstrated that student interaction outside of the lab time was the strongest predictor of positive student attitudes toward group learning. Student perspectives on group formation are mixed, and suggest that a simple and flexible choice approach may best support our students. Overall, these findings have clear implications for our course design and instructional choices: we should focus our efforts to promote positive student interactions, rather than worrying about initial composition.

中文翻译：

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在实验室中支持学生的学习和经验：（如何）我们应该设计他们的小组？

理科本科生花费大量时间在他们的实验室小组中工作，而指导教师希望就如何最好地建立这些小组做出循证决策。尽管对组的组成进行了数项研究，但证据似乎是针对特定环境的，关于实验室组的文献很少。此外，许多研究仅专注于概念学习。但是，实验室是一个重要的场所，也可以支持诸如信心，流程技能，团队技能和态度等非内容性结果。因此，在分子，细胞和生理学入门课程中，我们对小组组成对学生成绩分布的影响感兴趣。学生要么被导师分组，要么自行选择分组。要评估小组组成对学生成绩的影响，我们在2个学期内从500多名学生那里收集了前/后数据。我们的措施评估概念知识，对实验室技能的信心，对小组学习的态度，实验室成绩，性别，学习年份以及（通过开放式问题）学生的观点。使用多元回归方法，我们建立了基于学生的个人属性和实验室小组属性预测学生成绩的模型。令人惊讶的是，初始组的异质性/同质性，以及这些组是由学生选择还是由教师选择，都不会影响这些模型中的学生成绩。进一步的MANCOVA分析表明，在实验室时间以外的学生互动是学生对小组学习的积极态度的最强预测因子。学生对小组形成的观点参差不齐，并建议一种简单灵活的选择方法可以最好地支持我们的学生。总体而言，这些发现对我们的课程设计和教学选择具有明显的含义：我们应该集中精力促进学生之间的积极互动，而不必担心最初的写作。