The research aimed to identify the effect of using mental strategies supported by practical performance on some psychological skills, stress management, and the level of technical performance of my skills (forward somersault on the hands and landing standing on the mattresses higher than the table - the side somersault with a quarter of a turn and landing standing on the mattresses higher than the table) on a table device Jumping for gymnastics juniors under (12) years old, and the researcher used the experimental method on a sample of (10) gymnastics juniors under (12) years old. Mental Strategies Program. The most important results: 1- The use of mental strategies (thinking about the skill assignment - positive self-talk) has a positive, statistically significant effect at the level (0.05) on the psychological skills (the ability to relax - mental visualization - focus attention) among the members of the main research sample. 2- The use of mental strategies (thinking about the skill assignment - self-talk) contribute positives to directing tension to the optimum level for gymnastics juniors under (12) years. 3- Using the mental strategy contributions to improving the level of performance of my skills (forward somersault on the hands, landing on the mattress higher than the table - side somersaulting with a quarter of a turn and landing standing on the mattress higher than the table) on the vaulting table device for gymnastics juniors under 12 years old. 4- There are improvement rates for the dimensional measurement over the tribal measurement of the basic research sample members in the psychological skills and levels of muscle tension under research with a percentage ranging between (9.14% - 36.73%). 5- There are improvement rates for the dimensional measurement over the tribal measurement for the members of the basic research sample in the level of performance on the jumping table device with a percentage of (11.66%).