The ideology of most schools in America is to teach all the information throughout the semester having quizzes or projects as you progress, leading up to one cumulative exam. This practice has been heavily scrutinized and tested around the country and the world. There is no one correct way to teach or to learn, but this article gives an interesting take on the effects of pretesting and how the average person learns.
We should be encouraging students to learn and grow for their betterment, not for a better GPA.