Dear Beatbox-Bandit,
Your quant score could be an issue; it depends on the schools you are targeting and how the rest of your application looks (i.e., how much & how you did in quant courses in college, how much analytical/quant work in your professional experience, etc.). Increasing your GMAT quant is certainly one option, as is taking some math courses. In assessing your entire profile and app against your target schools, you should get a sense for which is best or if both are necessary. For instance, taking math classes might not add much if you have significant quant coursework in college where you earned high marks. Conversely, if you have minimal quant coursework, then taking math classes and earning A's would strengthen your application.
Good luck,
Lisa
