Now I haven't done the courses that you are challenging, but I have successfully passed 5 other CLEP exams, on the first attempt.
I tried several resources when I studied for my exams. There were only two resources that I thought were worthwhile. 1) I used this
online resource. It is a pay service to use, but it has a 30-day money back guarantee, and it is well worth the cost in my opinion. It covers all the key points and should get you up and running on your topic. You want to be scoring better than 60% on the practice tests before you move on to 2) the official CLEP practice test book
. You can buy this book that is one edition back from the most current one for about $6. They really only change one or two questions per section, in the newer issue. Again, you want to be scoring better than 60% before you move on to take the CLEP exam. I am sure that I saw a few questions from the practice book that were on the real test verbatim.
Best of Luck