Table 1 Summary of exam data collected in years 0 to 3 from introductory chemistry, physics, and biology courses.

A detailed summary by course is provided in table S2.

DisciplineCourse sections
offered
Unique instructorsUnique exams
coded
Questions coded*
Individual
questions
ClustersTotal
Chem I and II49213271893811
Phy-A and Phy-C I and II783534479230709
Bio I34204017051841899
Bio II2492852883611
Total1858713434305904020

*When the same question was used on different exams (by the same or a different instructor), it was coded every time.