This case study is an example of a formative evaluation over a multi-year period. Formative evaluations are used by teachers to modify teaching and learning programs with a focus on improving student understanding. Evaluation forms were completed by 1949 students who attended five different biological science courses within seven years. The assignments that students worked on changed from year to year and were different for each course. Each year, the instruction changed in terms of content and delivery. Nevertheless, the learning outcomes did not change.