I took the TEAS with no previous sciences and passed with an 82, so it is possible. And I haven't been in school for a very long time! I used several manuals, but I found the official TEAS book to be the most helpful, especially because it gives you practice tests in the back of the book. I also agree with Kahn academy online and youtube has some great videos on lots of subjects. Some of the youtube videos helped me understand the material better than anything else. Just study as much as you possibly can between now and your test. Best of luck!