The International Association for the Evaluation of Educational Achievement's (IEA) mission is to enhance knowledge about education systems worldwide, and to provide high-quality data that will support education reform and lead to better teaching and learning in schools. In pursuit of this aim, it conducts, and reports on, major studies of student…

An observational study of 12 mixed-age and 12 single-age Dutch primary reading/language and mathematics classes revealed that time-on-task levels were lower for the mixed-age classes. However, no significant differences in achievement test scores were found. (IAH)

Lessons in values development were observed in classes of Dutch students, aged 10-15. A 22-item observation instrument was used to record the amount of classroom time spent on a particular category. Factors which affected students' behavior included nondirective versus directive teaching behavior and certain questioning techniques. (GDC)