فاعلية استخدام نموذج فان هيل (van hiele) لتدريس الهندسة على التحصيل الدراسي لدى طالبات الصف الثاني المتوسط بمدينة نجران
The study aimed at identifying the extent of effectiveness when using Van Hiele's model in teaching geometry on the 2nd intermediate female pupils' learning achievement in Najran City. For achieving this objective, a quasi-experimental approach was used by the researcher represented in designing an experiment with pre- and post-tests. The sample of the study was composed of 58 female pupils of the 2nd intermediate grade in Najran City who were divided into experimental and control groups, 29 pupils each. The experimental group were taught the topics of Geometry and Spatial Reasoning unit by using Van Hiele's Model. While the control group were taught the same topics using the traditional method. Then, a research tool was administered (i.e. Achievement geometry test) to both groups producing the following findings: There was a statistically significant difference at (0.01) between the mean scores of the experimental group and the students of the control group in the post-measurement of the achievement test at the level of (recall, understanding, application) and its levels as a whole for the benefit of the students of the experimental group. Based on the findings of the study, the researcher introduced a number of recommendations of which the significant one was: training female teachers in using Van Hiele's Model when teaching mathematics in general and geometry in particular. (Published abstract)