|Franke, G; Bogner, FX: Cognitive influences of students’ alternative conceptions within a hands-on gene technology module, The Journal of Educational Research(104), 158-170 (2011)
In a German out-of-school laboratory, 293 medium achieving 10th graders participated in a lesson unit about gene technology. Divided into two groups (I-1, I-2), both of which followed the same hands-on lesson procedure. Students within I-2 were additionally confronted with alternative conceptions to central issues of the specific topic. We monitored cognitive achievement, mental effort and calculated the efficiency of instructional conditions. Knowledge scores increased significantly in both groups in the long-term. In the short-term, I-2 showed significantly better results. Also, these students needed to invest a significantly lower level of mental effort during the interpretation phase. Instructional efficiency differed in the short- and the long-term. Students within I-2 showed either the same cognitive achievements with lower strain, or higher ones with the same strain.