Additional survey VOCL'93 - Cohort Survey of Secondary School Pupils 1993 by the Central Bureau of Statistics -, in order to get insight in the extent to which differences in achievements and progress in Dutch and mathematics may be explained through characteristics of pupils, teachers and schools. Decision-making of parents and pupils about e.g. coming home, having a job on the side, drinking alcohol, watching tv, follow-up courses / family-environment / parent-child relationship / time-spending of pupils after school hours / self-perception / opinion of pupils about their teachers, their classmates and school rules / expectations for the future / religion.