High-quality formative data can do more than tell us who “got it” and who didn’t! In this asynchronous session, educators will learn practical approaches to collecting and analyzing evidence of student reasoning to inform responsive instruction. Participants will explore approaches to classifying and grading student responses, practice interpreting misconceptions and partial understandings; and design quick but powerful checks that illuminate thinking, not just recall. By the end of the 6-week course window, participants will demonstrate their learning by submitting a short mini-project that they can put into practice immediately. Participants will receive access to materials on February 23 and submit their mini-projects on or before April 6.