The idea of "grouping" in schools ranges from group teaching to grouping of pupils, with many variations on these two themes. The self-contained classroom, found usually in the elementary grades, consists of one teacher with one grade-level class for the full day and for all subjects. The departmental approach, found at all levels, employs teachers to teach a particular subject or two only, and the pupils, during a school day, move from class to class. Team teaching occurs when two or more teachers share in teaching one particular group of students, usually in just one curricular area. Nongraded instruction enables students to advance in the curriculum according to their individual capacities. Perhaps most research in the grouping area has involved ability grouping, in which students of a given grade are divided up according to degree of ability or achievement. Other within-grade organization has been attempted; for example, planned heterogeneous grouping and teachability grouping. The research in many of these areas is inconclusive and incomplete and fails to determine the contribution of the organizational plan being examined. (WD)