Here is a concise list of must know topics for doing well on the ACT:
1. Slope formula
2. Distance formula
3. Midpoint formula
4. Equation of a circle
5. Equations of lines (parallel and perpendicular)
6. Area and volume formulas of common shapes
7. Pythagorean theorem and Pythagorean triples.
9. Rules of exponents
14. Trigonometry(soh cah toa)
15. Special right triangles 30-60-90 and 45-45-90
16. Multiplication counting principle
17. Percentage problems
19. Graphs of lines and inequalities
20. Reading and interpreting charts and diagrams.
The key to doing well on the test is RECOGNIZING what the problem calls for and knowing which of the concepts above to apply. This is where experience makes all of the difference. I tutor students on the math section of the test and what I do is have them take a number of ACT tests on their own and then after each time we go over the ones that they miss and I point out what concept is DISGUISED in the problem and a more direct way of solving it. The experience gained is very valuable but it is experience that has to be gained by the student themselves through EXPERIENCE with the test and wrestling with the problems and learning when to apply the various topics mentioned above. This I feel is the best way to spend one's time in preparation for the math section of the test. Again, I am very familiar with the test and have helped many students improve their score but there isn't any secret beyond knowing the key topics and taking a lot of practice tests and have someone point out what to look for and apply to the ones that you miss. Someone just informed me today that their score went up a full 7 points since I started tutoring them. They put in the effort and there is still room for even more from this particular student.
This could be my shortest blog yet.
Practice, then practice some more!
Experience with the test, in my opinion, will help you more than anything else. If you take a number of timed practice tests on your own and see which problems you are missing I can show you how to approach and solve those problems. When you see similar problems you will know how to do them. Remember, the ACT is a concept based test not an intelligence based test. Also, you may find it interesting to know that the entire test can be done without a calculator ...but of course you are free to use one as well. My highest recommendation is to start taking practice tests on your own, see which ones you are missing, review those concepts and repeat. I could tell you all kinds of neat tricks like picking the letter b when you don't know the answer but at best these strategies will likely only add a couple of points to your score. If you are reading this you want to see a jump of 5 or more points, right? Many students resist doing additional work over and above their normal homework load so figure out what type of weekly time commitment you can make and commit yourself to it.
Helping students succeed in math for over 15 years. Individualized attention makes the difference!