In the present study, we examined the effects of feedback that corrects and contrasts a student's own erroneous solutions with the canonical, correct one (CEC&C feedback) on learning in a conceptual change task. Sixty undergraduate students received expository instruction about natural selection, which presented the canonical, scientifically accepted account in detail. Two-third of these received CEC&C feedback on their self-generated solutions to open-ended test items. Students either received this feedback on their pretest solutions (prior to instruction), or on their immediate posttest solutions (following instruction). Students in the control condition only received the correct canonical answers to the immediate post-test items and compared these with their own solutions autonomously. Conceptual understanding on transfer items was assessed after 1 week. Results showed that students in the CEC&C feedback conditions outperformed control students. Timing of feedback did not affect learning, however. These findings add to accumulating evidence from different lines of research on the importance of instructional support that explicitly compares and contrasts between erroneous student models and canonical models in conceptual change tasks.