TEAS test

I bought the ATI book, which was useful, and took a bunch of free practice tests. That's pretty much it. I was better prepared for the science part than I would normally be because I took several classes last summer (bio, micro, A&P), but if I hadn't, I would need to learn all the organ systems, cell structure, and basic chemistry stuff. It was still the hardest part for me. The math is basic high school math--nothing super challenging, but make sure you're familiar with fractions, percents, mean vs median, etc. The reading can be tricky: mostly they want you to be able to extract the main point/purpose of a passage, so make sure you know the difference between persuasive, expository, narrative etc. kind of writing.

As for the grammar section, half is easy if you speak good English, but there's some very tricky grammar stuff that I was never taught (compound vs complex sentences, for instance!). But since it kept coming up on the practice tests, I learned it and did fine.

To be honest I didn't study THAT much, but I found the book and practice tests really effective and useful. Stuff I studied and learned for the test actually appeared on the test, unlike on most standardized tests I've taken... GOOD LUCK