Changes in Students' Understanding of Evolution Resulting from Different Curricular and Instructional Strategies

This study assessed students' learning of evolution by natural selection within four different sections of an introductory biology course. Each section used a different combination of curricular materials (either traditional or historically rich materials) and instruction (either paired problem solving or traditional lecture). Students in the study completed pre- and postintervention evolution tests. Students' responses were analyzed to create variables for both correct and alternative conceptions of evolution. Pretest and posttest data were used to create difference scores that were compared both within and between teaching sections. Pre-to-post gains were expected in the correct (Darwinian Conception) scores, while pre-to-post losses were expected in the Alternative Conception scores. Also, students in the experimental sections were expected to perform better than those in the traditional sections. Pretest-to-posttest differences within each section showed gains in correct conceptions but few reductions in alternative conceptions. Comparisons between sections support the use of the paired problem-solving instructional strategy in conjunction with the historically rich curriculum.