New Math
All of the New Math projects emphasized some form of discovery learning. Students worked in groups to invent theories about problems posed in the textbooks.  Materials for teachers described the classroom as "noisy."  Part of the job of the teacher was to move from table to table assessing the theory that each group of students had developed and "torpedoing" wrong theories by providing counterexamples.  For that style of teaching to be tolerable for students, they had to experience the teacher as a colleague rather than as an adversary or as someone concerned mainly with grading.  New Math workshops for teachers, therefore, spent as much effort on the pedagogy as on the mathematics.