I just took the test today and the science was very difficult for me. I spent lots of time studying everything in the ATI study guide and that certainly wasn't enough for me to do above average. I recommended to anyone taking it to go online and study the topics in the manual in much greater detail, as most of the questions required critical thinking. For students who are fresh out of micro and chemistry it will likely be much easier. For the rest of us, the manual is much too vague for the questions asked, IMHO.