Mathematics is one of those subjects that is learned alone. Lectures are the dominant mode of teaching.
Homework is done at one's desk.
Group projects are few and far between. When it comes to math, you may be sitting in a classroom full of other people, but that's where the sense of community usually begins and ends. For centuries, that has been the case. Cooperative learning encourages students to work, study, and learn in small groups, usually two to five people. In small groups, students feel more at ease asking questions and trading ideas, which they might hesitate to do in a more formal setting.