One of the best things you can do to prepare for college and the working world is to take a strong academic program in high school. College admissions counselors view a student's high school coursework as very important in deciding whether or not to enroll a student.
You should be in good shape if you take the following courses:
Check admissions requirements at colleges you're interested in to compare academic requirements to the ACT list. Your colleges may want you to take additional or different courses.
Always take the most challenging courses you can take. This will show colleges that you are willing to work hard to learn and that you are not just doing what it takes to get by. Colleges will be more impressed by respectable grades in challenging courses than by outstanding grades in easy ones.
Source: ACT, Inc.