Math and science are learned by doing
Practice problems are the primary means through which you will learn course content in quantitative courses. Making the best use of problems will help you learn as quickly as possible and be well prepared for tests.
Misusing practice problems is a waste of study time and can lead to a false sense of mastery and/or confidence.
Start with the problems that were done in class
(Ideally) without looking at the solution in your notes, re-do any problems that were demonstrated in class. Do this within 24 hours of lecture to prevent forgetting and store what you learned in class in your long term memory.
Study in short, frequent sessions
You will learn most by taking short breaks every hour and studying a little every day. Cramming is always a bad idea, but it is especially ineffective for quantitative courses.
Stop solving easy problems
If you start working on a problem and see that it’s easy for you, STOP. Go on to a harder problem.
Do lots and lots of problems
Learning university-level math and science is hard work and takes a long time. Many students need to do more than the assigned homework to master the concepts taught in class.
Only you can judge whether you’ve truly mastered a concept – don’t assume that just because you’ve done the assigned problems you’re necessarily ready for the test.
Do problems from different sources
Just like writers of novels, problem authors have different ‘styles’. Solving problems from lots of different sources introduces you to different styles, so you won’t be thrown off when the midterm problems have a different author than the textbook problems.
Find extra problems in previous or practice exams, other textbooks (look at the library, SFU bookstore or other college/university libraries), or web sites (e.g.: the Khan Academy or MIT Open Courseware).