Fig. 4

Several lessons in the Natural Selection module explore a population of stickleback fish. In the “Loberg Lake Stickleback Data Collection” simulation (left), students gather samples of fish at three time points and arrange them on a graph according to their numbers of lateral plates. An accompanying teacher website (not shown) randomly distributes the data to each student, controls students’ progression through the simulation, and aggregates the data from all students to generate a class bar graph for each sampling period. The “Natural Selection Checklist” argumentation scaffold (right) helps students organize evidence from this activity and others in the module, preparing them to write an evidence-based argument