This study aimed to investigate the plenty degree of performance evaluating tools for school supervisor which depend on management grid theory for practical studies at middle stage in Kuwait state from their point of view. To achieve the study goals the researcher built a questionnaire which consisted of (24) items according to management grid theory and disseminated it to (16) school supervisors for practical studies in Kuwait city to collect data. The study discovered that the plenty degree of performance evaluating tools for school supervisor which depend on management grid theory for practical studies at middle stage in Kuwait state from their point of view was high. And there was no statistical differences in school supervisors for practical studies point views to the plenty degree of performance evaluating tools for school supervisor which depend on management grid theory for practical studies at middle stage in Kuwait state from their point of view attributed to the Experience. The study recommended that school supervisors should have information about evaluation staregies.