The second time, I purchased the Morrison Media flash cards. They helped a
ton but I have to warn you, it seems a little intimidating just by the
sheer number of cards. If you have a month or two to go, they are really
good but you've gotta keep working with them. If you've only got a few
weeks, it may be too much material and you could find yourself bogged down
with info. I also used Barron's AP test guides for US History, World
History, and Government to break up the monotony. All very helpful and I
would recommend them.
Hang in there and good luck to everyone getting ready to take this test.