The progress of students under 21 years old at the United Kingdom's Open University (OU) was compared with a sample of mature students, using sociological and psychometric research methods. The research goal was to consider whether the OU's teaching system originally designed for adults is suited to the needs and circumstances of students in the 18-20 age group. Additionally effort was directed to developing predictive indices of success and failure at the OU and to assess the level and nature of demand for OU places from the younger age group. Postal questionnaires, personal interviews, and administrative and academic records were used to monitor their progress, to measure their reactions to courses, and to discover their reasons for withdrawal. Groups of entering younger and older students completed a sociological questionnaire and a battery of psychometric tests. Findings include the following: the pilot scheme for attracting younger students attracted very few 18-year-olds and even fewer school leavers; the younger students fared less well than older students in their first year of OU studies; and younger OU students tended to score lower on the intelligence test than did older OU students and younger students elsewhere in higher education. Among the factors that appeared to underlie the relatively poor performance of the younger students are the following: instability, finance, time pressures, and attitudes. Some policy implications for OU are considered. (SW)