I just completed the class with New England Maritime and think highly of the program, although it's alot of time... 3 nights a week Jan/Feb and a couple Saturday's for FirstAid/CPR, etc... They provide you with software that has about 30 practice exams on Rules, which is tremendous. I also found this site which has flashcards for Rules along with some powerpoint slides on Plotting and Marlinspike. The flashcards are painful to print correctly, but helpful nonetheless.
www.ship468.org/advancement/able/
I take the exam in a couple weeks, so let's see how helpful all this really was...
Later, Kevin