AP Calculus AB is the coolest.  It will be a challenging class, but the trick to overcoming the challenges is to form a study group with reliable kids.  This course will tie together all your geometry, algebra, and trig skills.  If you are weak in these areas, don't worry.  You will get lots of practice.

The grade is determined from quizzes and tests.  The quizzes are just your average 20 point quiz.  These will make up 35% of the grade.  The tests usually take two days.  The first day is the multiple choice part.  The second day is the free response part.  This is the same format as the AP exam.