Schools fail to develop students' unique capabilities mainly because of large-group instruction limitations. Mutual Instruction (MI), a comprehensive peer assistance program involving all students in cross-age tutoring and counseling, is a sound and practical approach to restructuring the conventional lock-step, assembly-line program. Teaching--or helping others learn--is an essential learning experience benefiting both tutor and tutee. The main features of comprehensive MI schools include: (1) elmination of age-graded classrooms and normative grading, allowing students to progress at their own pace; (2) teachers working one-to-one with students to plan individualized programs and with small groups on cooperative learning projects and tutoring instruction; (3) inclusion of all student age groups (5-18) on the same campus; (4) provision of facilities for early childhood care and preschool development programs; (5) provision of well-staffed departmental study rooms and labs for each subject area; (6) a year-round operating schedule without scheduled classes; (7) membership of each student in an "MI family" of 25 schoolmates of all ages; and (8) the pursuit of enrichment in art, music, drama, sports, and special intellectual interests made possible by the efficiency of MI in cutting the time needed for mastering basic curricula. Included are comparison charts, an opinion survey, two appendices containing, respectively, an MI proposal and a narrative description of an elememntary MI school, 25 endnotes providing annotations on 40 references, and an annotated list of recommended reading including notes on ERIC reference sources. (MLH)