Assessment of self-explaining effect in a large enrolment General Chemistry course

Self-explaining refers to the generation of inferences about causal connections between objects and events for one's own consumption. Self-explaining is amongst the practices of science deemed essential for scientific competence; therefore, a valued learning outcome in itself. Nonetheless, generation of authentic explanations is seldom promoted in college science instruction. This work examined the effect of engagement in self-explaining on conceptual understanding of chemistry. Learning and performance tasks were completed individually in the classroom ecology of a large-enrolment General Chemistry course in the US. The study spanned a period of five semesters including pilot-tests and replications. The self-explaining intervention followed a multi-condition comparison design that used performance on a post-test to assess learning. Students were randomly assigned to the following conditions: reviewing a correct explanation, explaining correct or incorrect answers, explaining agreement with answers produced by others, and explaining their own answers. A cohort of students who underwent standard instruction with no intervention and had prepared for formal examination served as reference. The self-explaining cohorts performed better than the reference group, and in one case was the difference statistically significant. Findings suggest that self-explaining activities support students’ conceptual understanding at least as much as instruction. This study contributes evidence for the self-explaining effect and the ICAP hypothesis in a discipline where no evidence is available. Furthermore, it adds to the relatively little work in self-explaining that has explored naturalistic learning environments. This work supports the incorporation of self-explaining activities in the repertoire of instructional practices for General Chemistry.