Featured in this yearbook are twelve thematic essays that analyze and interpret organizational alternatives for teaching mathematics in the elementary and secondary schools. The following topics are covered: three different models for individualized instruction (Individually Guided Education, a departmental model, and a classroom model), independent learning units, small group work, simulations, mastery learning, organizing lessons based on logical considerations, integrated curriculum, the teacher-centered classroom, and implications of research for self-paced mathematics instruction. The final essay (non-thematic) describes four reports which include recommendations on the use of hand-held calculators in schools and cites examples of specific activities involving the use of calculators. (DT)