I don't know if someone has already suggested this, but it would be nice if the exercices had a way to draw/write on the test (like the normal exercises in khan academy, but maybe having few more features). Usually, these tests would be paper and pencil and you could write on these, highlight important text, etc. It would be great if this was possible for both reading (more than having just highlighting, and a choice to do it on the questions too) and mathematics. This would certainly help many students including me. Thanks!