Image 4
Every class was staffed with two instructors and three assistants (one instructor, one graduate student, and two undergraduate students.) The instructors and assistants circulated around the room to see how students were approaching the problems and where students were getting stuck. When helping, we paid extra attention to groups that were struggling to make progress and sometimes asked more challenging follow-up questions to groups that finished quickly. We wanted to get everyone to about the same point so that we could discuss the solution productively as a class.
In most introductory-level math courses at MIT, problem sets include a mix of drill problems and more challenging problems. Because we worked through so many problems in class and to some extent on the reading questions, we were able to focus the problem sets on challenging problems.