The purpose of this study is a recognition of factors affecting educational achievement. The target population consisted of 194 students of Agricultural Faculty of Tehran University. The relaibility of questionnaire through Kronbakh test (individual and family charactristics of students %84, educational and scientific skills of the faculty %87, the content of curriculum %83, the charactristics of environment %85) was verified. The results indicated significant correlations between educational achievement and high school diploma average, hours of studying, educational programme, motivation, emotional environment, aim as well as family's attitude. Results indicated that girls benefitted from a more pronounced educational achievement as compared with boys. There was no significant difference observed between the students who lived with their family or in dormitory. The study showed that agronomy major achivement of students were the most successful among the eleven major students. Regression analysis revealed that %63.5 of the educational achievement variance among students was determined by the five variables of: diploma average, motivation, educational skills, father's education and finally emotional environment.
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