فاعلية منصة ادمودو (edmodo) التعليمية في التحصيل وتنمية الدافعية لدى طالبات الصف الثالث المتوسط بمقرر الرياضيات
The study aimed to identify effectiveness of Edmodo as an educational platform on the achievement and the development of motivation of the intermediate- third class female students in the mathematics course. To achieve this aim, the study was conducted in the first semester of the academic year (2017/2018), on a sample of (66) female students from the Intermediate- third class in Al-Madina Al-Munawara. The sample was divided randomly into two groups: an experimental group (which was studied using the Edmodo educational platform) that contained (33) students and a control group (which was studied in the usual way) that contained (33) students. Semi-empirical method was used, which based on the tools represented on the achievement test, the motivation scale, the Edmodo educational platform and guide indicative the use of the platform. After measuring means, standard deviation, t-test and calculation of effect size equation, the study showed a statistically significant differences between the mean scores of the two groups in the post-achievement test, in favor of the experimental group, and between the means scores of the preand post- measurement for experimental group in the achievement test and the motivation scale, in favor of the post-test. The study also showed that the effect size of Edmodo as an educational platform on the achievement and the motivation development was high. In the light of the results, this study found that Edmodo as an educational platform could have an effectiveness on the achievement and the development of motivation of female students. Finally, the study recommended to the expansion in applying educational platforms, which include Edmodo educational platform, in different stages and stimulate the teachers to use them in learning. (Published abstract)