First, let's look at regular attendance. It sound simple. But it's actually very important. Dr.Claude Olney did one study of 800 students. He found that on average, student who got As missed less than one class per term, and people who got Cs missed more than four class per term. In class, teacher explain difficult ideas and make clear information is most important. Student teacher discussion gives an in-depth understanding that can't come from books. Attendance is even more important for doing well on tests.