A Case of Early Positive Results in Student Gains: The Institute for Chemistry Literacy Through Computational Science MSP
4. Results
After one year of implementation, statistically significant gains in chemistry content knowledge were experienced among students of treatment teachers, compared to students of the control group. The means of student pretest scores for C1 and C2 teachers were not significantly different, indicating the similarity of baselines and demonstrating the comparability resulting from the random selection of teachers into treatment and control groups.
However, the mean gain (difference between pretest and posttest scores) after seven months in the classroom for Cohort 1 was 9.8 percentage points, compared to 6.7 percentage points for Cohort 2. This statistically significant difference (p<.001) represented an effect size of .25 standard deviation units and indicated unusually early confirmation of treatment effects. When posttests were compared, Cohort 1 students scored significantly higher than Cohort 2 and supported the gain score differences.
Student content knowledge gains occurred in a context of teachers themselves not experiencing comparable gains over the period examined. Delivery of college-level ACS chemistry tests to teachers showed no difference between cohorts either in overall scores pre and post testing, or in changes between pre and post scores.
However, the mean gain (difference between pretest and posttest scores) after seven months in the classroom for Cohort 1 was 9.8 percentage points, compared to 6.7 percentage points for Cohort 2. This statistically significant difference (p<.001) represented an effect size of .25 standard deviation units and indicated unusually early confirmation of treatment effects. When posttests were compared, Cohort 1 students scored significantly higher than Cohort 2 and supported the gain score differences.
Student content knowledge gains occurred in a context of teachers themselves not experiencing comparable gains over the period examined. Delivery of college-level ACS chemistry tests to teachers showed no difference between cohorts either in overall scores pre and post testing, or in changes between pre and post scores.
