While you are still in high school, be sure to take as many science and math classes - especially biology and chemistry. These high school classes will prepare you for your college math and science classes. As a pre-med college major, you will have the opportunity to take various biology and chemistry courses such as microbiology, organic chemistry, biochemistry, etc.. You will also have labs for many of these classes. Keep in mind that if you decide to major in pre-med or biology for college, your courses will be listed out for you by year and semester. It may be a good idea to go to the website of a college/university and look at the courses that they have listed for biology/pre-med and be sure to read the desriptions of the courses.