Differences in family factors in determining academic achievement were investigated by testing 432 parents in nine independent, coeducational Melbourne schools. Schools were ranked and categorized into three groups (high, medium and low), based on student achievement (ENTER) scores in their final year of secondary school and school improvement indexes. Parents completed a questionnaire investigating their attitudes towards the school environment, their aspirations, expectations, encouragement and interest in their child's education (adapted from scales constructed by Marjoribanks). They also responded to six open-ended questions on their attitudes to achievement and to their (child's) school. Multiple regression analyses revealed that parental expectations of their children's educational level made the strongest unique prediction of high achievement followed by the length of time they had maintained their expectations. Limitations discussed include the disparity in meaning associated with the definition of school success and whether these results can be generalized to all students considering the biased sample (socio-economic status).