The Effects of the activities designed with respect to the Van Hiele model on students' achievement and attitudes

This study was conducted in an elementary school in Bolu during 2005-2006spring semester. Sample of the study consisted of randomly selected two sixthgrades classrooms. One of the classrooms was selected as a control group and theother was selected as an experimental group. In the study, Control Group PreTest-PostTest Experimental Group design was used. In experimental group, activitiesdeveloped using Van Hiele geometric thinking model were used whereas in controlgroup traditional teaching method was used. In order to determine students?geometric thinking levels, achiement and attitudes before and after the treatment VanHiele Geometric Thinking Test, Geometry Achievement Test, and GeometryAttitude Scale were used, respectively.In both groups, a unit on angles and triangles was taught during 3 weeks (12hours). In the experimental group, activites developed with respect to the the VanHiele model of geometric thinking were implemented. During these activities,worksheets were distributed to the students and they worked on them as a group,after group works they shared their results. Whole class disscussion of the activitiesfollowed the group works. In control goup, teacher used the lecture method. In bothgoups, the researcher was the teacher.Pretest and posttest scores of each group was determined and comparisons ofthe mean scores was done using t-test. The significance of the difference between themean scores was evaluated at 0.05 level.Results showed that the geometric thinking levels of the students in theexperimental group showed more progressed than that of the control group. Inaddition, geometry achievement in the experimental group was higher than thecontrol group. Moreover, students? attitudes toward geometry in the experimentalgroup showed significant progress than in the control group. These results suggestthat when geometry teaching is based on van Hiele model, the students? successrelated to the angles and triangles and also their attitudes toward geometry get better.Key Words: : Geometry, Van Hiele Model of Geometric Thinking,Attitudes.