It helped to have a purpose or something to accompany it, e.g making a game as that would require a bit more math than CRUD apps.
This helped me brush up on some (embarrassingly simple) vector math http://natureofcode.com
It was great when I was working aeronautics as the modeling and simulation required a thorough review of theories and concepts. These days, I'm lucky to do more math than built in excel functions... Again, /sad.
Please, stop. I always cringe over how embarrassingly poor my math is compared to most that I don't even dare to venture out of 2d unless it's for simple UI transforms even then I struggle because of no firm grasp over some of the concepts.