We thank the course instructors and students who participated in the project. This work was supported through a National Science Foundation Transforming Undergraduate Research in the Sciences (TUES) grant (NSF no. 1323258). We thank our collaborators on this grant, including Jane Cameron Buckley, Brian Couch, Mary Durham, Jennifer Frederick, Monica Hargraves, Claire Hebbard, Jennifer Knight, and William Trochim. Support for the Summer Institutes on Scientific Teaching was made possible through funding from the Howard Hughes Medical Institute originally awarded to Jo Handelsman. We appreciate the helpful comments and suggestions from three anonymous reviewers.