The analyses of achievement test
In this part, the findings emerging from the statistical analysis of data collected were analyzed according to the research problem. Before the research, pre tests were applied to both groups to determine whether the levels of the students ' knowledges about GCD-IPPC in experimental and control group are similar or not. After pre-test, then,main scores of groups of arithmetic averages, standard deviations, and whether there is significant difference between means was calculated by independent t -test. The datas obtained are shown in table 1.