Given the expense, time and considerable teacher effort required to perform hands-on activities in the classroom, their consequences for student learning need to be evaluated. This study takes one example of student-active learning, students collecting and analyzing their own data, and asks whether the physical act of collecting data increases students’ learning of natural selection and affects their enjoyment of science activities. On both pre- and post-tests the number of correct responses on multiple choice questions was low in both treatments, although the number of equivocal responses did increase over time. Essay question responses were generally poor and similar across pre- and post-tests in both groups; however, after the simulation, students in the activity group showed a more sophisticated understanding of the inheritance of adaptive traits. Overall, the generally poor performance indicates that the three weeks designated for students to learn evolution as an isolated topic within the Philadelphia curriculum is probably not an adequate amount of time and should be expanded. Our strongest finding is that participation in the simulation activity caused students to have a much more positive assessment of science activities. We propose that teachers should take advantage of this and purposefully choose activities that will engender positive attitudes towards science while teaching content knowledge.