FIGURE 3.

Experimental design skills observed on pretest and posttest for students in (A) introductory biology (N = 59 students from three courses) and (B) upper-level biology (N = 86 students from six courses) courses in study 1. The observed experimental design skills are the percentage of students whose response to the EDAT prompt included a given rubric category. The categories on the x-axis represent the EDAT scoring rubric items (Table 2) listed in the order of experimental design sophistication (Sirum and Humburg, 2011). Categories in bold font are components of the basic understanding score, and those in capital letters are components of the advanced understanding score based on Shanks et al. (2017).