Two time periods of Quizzical participation were monitored and their relationship to two term test dates (circled) are shown on the left panel (2017 data only, as an example). The second panel shows box plot data related to term test 2 scores in 2017. Students who participated less often in period 2 compared to period 1 are Group 0 (G0), whereas students who participated more in period 2 vs period 1 are Group 1 (G1). The other box plots show data for comparable periods for the final exam (2017 TT3) and comparable data from 2018 (plots 3 and 4). Paired T tests revealed statistical significance for all pairwise comparisons of G0 and G1 data (p-values are 0.03929, 0.0212, 0.0038, and 0.002, respectively).