The authors thank the Automated Analysis of Constructed Response (AACR) collaboration for helpful conversations while preparing this manuscript, especially Drs. Megan Shiroda, Alex Lyford, and Jennifer Kaplan. We also thank the SimBio content team for preparing a version of the Cellular Respiration Explored tutorial to be used in this study and thank participating instructors and students. We also thank the editor and two anonymous reviewers for their helpful comments. This material is based upon work supported by the National Science Foundation (DUE 1323162). Details about the questions used in this study and accompanying predictive models to score new student responses, can be found at beyondmultiplechoice.org.