Research on children at risk for school failure emphasizes the need to understand the ways in which pupils are engaged or disengage from class and school activities. This paper describes the development of a teacher rating scale that assesses the form and extent of participation among elementary grade pupils. The Student Participation Questionnaire was tested with a large sample of Grade-4 teachers and their pupils. Three reliable scales were obtained and labeled (a) Effort, (b) Initiative, and (c) Nonparticipatory Behavior, along with a short scale that reflects the extent to which the student values school achievement. Analysis of variance of the subscales indicated that females, pupils from homes with higher incomes, and nonminority pupils generally participate in the classroom more than their peers, although there is some confounding of the race and SES effects. The instrument should prove particularly useful in further research on student involvement.