All data were consolidated into a single Microsoft Excel spreadsheet, filtered for anomalies, and uploaded into PASW (previously SPSS) Statistics 21. Because participants were not randomly assigned to control and treatment conditions in this study, it was important to establish comparability of the groups on the available exogenous variables, which included aptitude variables (composite ACT score, GPA)and demographic variables (ethnicity, sex, age). Descriptive statistics were therefore compiled for each of the three classes to generate a profile of each sample, and appropriate tests for equivalencies between the groups were run to determine whether the control sample varied significantly from each of the treatment samples (Tables 1 and 2).