" Competitive Differentiation And Its Impact On Self-Esteem And The Development Of The Offensive Wall Skill In Volleyball" * Dr. Manar Mahmoud Abdel Salam Shaaban  The researcher conducted a study entitled "Competitive differentiation and its impact on self-esteem and the development of the offensive wall skill in volleyball." It is measured by the objective test of the offensive wall skill (quantitative evaluation) - the form of technical performance and it is measured by the performance evaluation form by three referees (prepared by the researcher) (qualitative evaluation) - the self-esteem scale (current ideas). The researcher used the experimental method by following the experimental design with a pre and post measurement for three groups (high level, medium level, low level). The research community was selected from among the female students majoring in volleyball, the third year, at the Faculty of Physical Education for Girls - Zagazig University for the academic year 2021/2022, consisting of (174) students, 100% of the research community And the exclusion of (4) female students. The research sample was chosen in a deliberate, random manner from the third-year volleyball students, their strength is (170) students, and they were divided into (120) students who represent the main study sample. Before applying the basic experiment, and based on the grades, the students were deliberately divided into three levels (high - medium - weak) and (50 students) were randomly selected from outside the sample of the basic study and representative of the research community to conduct scientific transactions for research tools, and to conduct the exploratory study. The most important conclusions reached by the researcher indicated the positive impact of the proposed competitive differentiation program on the results of the self-esteem scale and the development of the offensive firewall skill among female students. There are statistically significant differences between the pre and post measurements for each of the research groups (high level, middle level, low level). In the results of the scale of self-esteem and offensive wall skill under research in favor of the post-measurement, there is a percentage of improvement occurring between the two measurements before and after among the research groups (high level, medium level, low level) in the scale of self-esteem and offensive wall skill, and the best percentage of improvement was due to the group Low-level group, then middle-level group, then the least improvement rate for high-level group., Competitive differentiation exercises contributed to raising the level of self-esteem and skill performance (quantitative and qualitative) for students of volleyball specialization, the third division of the three groups (high - medium - weak). Evaluating the technical performance of the offensive wall skill in volleyball to assess the level of female students (qualitatively) (prepared by the researcher), the need to take into account the psychological aspects of female students when training and teaching them the skills of sports activities in general and volleyball skills in particular, the application of a self-esteem scale to determine the student’s view For herself and work to develop it to get a higher self-esteem..