[matthewdgreen]

Lectures were originally created as a way to share a single book. Since printing was expensive, a reader would stand at a lectern and read the material aloud. You might say "why don't we have all the students share a single book, that worked fine" but the truth is it was a crummy solution to a resource constraint problem.

Similarly, exam-only courses are an excellent way to teach huge numbers of students without the costly hassle of grading homework assignments. But that doesn't mean they're an optimal solution.

From my experience as a student and now a professor, nothing can possibly compare to the benefit you get from hands-on learning. You get so much more understanding from the 20 hours you spent making a complex system work, than you will ever get in three 3-6 hours of in-class instruction you'd get during the same timeframe. And I have no good idea how to test for all the skills you learn from "writing a tiny OS kernel from scratch in C" or "building a compiler" or "implementing a complicated cryptographic protocol and then realizing an attack on it." I do observe that my students who do the homework tend to do much better on the exams, but I'm concerned that the incentive to take shortcuts will be much too high if homework isn't required.