I studied purely from the REA Biology Clep study guide, and I scored a 67 (50 needed to pass, 80 is perfect). I started with absolutely no knowledge of Biology, and I was able to pass by cramming for 3 days (about 4 hours per day). Therefore, if I were to reccomend a study guide without any kind of supplement, it would be the REA CLEP Biology Book. This book was very comprehensive, but there were topics covered in the test that I had not seen in this study guide.

I believe that if you have the capability to comprehend and apply concepts (not just memorize facts), you can do reasonably well on the CLEP with no other preparation than this guide. However, if you are the type who memorizes and has trouble generalizing/applying concepts, you may need more preparation that just this guide. That is a decision you will have to make for yourself. Consider reviewing a College-level Biology textbook along with this study guide for a more comprehensive approach.

I hope this review helps. Good luck with your test preparation, as the Biology CLEP is somewhat difficult.

I studied only from this book including taking practice tests and passed the bilogy with 63. The book gives good material on the topics, arranged systematically and writen in detail. I would completely recommend it.

Great book! Helped me study for an advanced placement exam. All the info was there

I recently passed the CLEP Biology exam (2/05) and found the book quite helpful, particularly the practice exams. However, I do recommend using another study guide such as an AP Biology book or Intro to Biology textbook.

In Callihan's book, the content depth is more appropriate for people who are somewhat familiar with the topics, or looking for a solid review. However if you are brand new to biology, then this book is probably not for you. The practice exams will help, but you'll need a much more comprehensive biology text.

I recently took the Biology Clep Exam (November 2) and scored a 48 (50 needed to pass). I studied for 2 months. I knew this book in and out -- the Sample Prep Tests 1-3 and the reasons why the other answer selections were not correct. However, I do believe you need to study another Biology book -- I felt maybe a handful of questions were questions I recalled from the Clep Study Guide and the others were foreign to me -- you really had to know your biology to answer these questions (i.e., quite a few case scenarios with charts and graphs). Good Luck!