What is the best prep book to study for AP Computer Science? I have been struggling at times in class and that makes me scared. I have seen Princeton, Barron’s, and 5 steps to 5 in the stores.
Barron’s worked amazingly for me. The practice tests and solutions were very clear and easy to understand. They explain concepts very well. I highly recommend it.
Got a 5 with Barron’s, btw 
Honestly, it really depends upon who you are and how you learn. I got a 5 as well, and used no review book. I simply focused on the projects(given by teacher) and the free responses. I had no prior knowledge about the subject.
My best advice is, take the previous years’ exams and time yourself(only do the ones you have learned so far). This is probably the most effective method for most students. Memorizing will not help you with this class; if you need a concept explained, ask your teacher or consult the internet.