Teaching biology in a group mastery learning mode: high school students' academic achievement and affective outcomes

Two learning units, the cell and plant topics were taught for seven weeks in four 10th grade classes. Two experimental classrooms (N=52) were instructed in a Group Mastery Learning (GML) method, and two comparison classrooms (N=61) in Individualized Mastery Learning (IML). For entry behaviour, data was collected on students' aptitudes (GATB), and their math and science scores. Students' pre- and post-tests scores on academic achievement, self-esteem, perception of classroom learning environment (CLE) and attitudes toward biology were tested using covariance analysis. Students in the GML classrooms had higher scores in self-esteem, attitudes toward biology, and in the sub-scales of the CLE. In the IML classes, a decline on these measures occured. Students in the GML method, scored higher in the cell unit, while students in the IML method scored higher in the plant unit. This result is discussed within the framework of the complexity of the learning units. (Autorenreferat).