Hey MA466,
Are you having problems with the verbal section of the gmat? I think if you're just struggling with the quant section, then you just need help in that area. Taking a class won't be worth the money if you are going to just attack one weak problem. There are only a couple of reasons I can think of why someone would do a course:
1) Weak in both quant and verbal and seriously need help in both
2) No commitment to sit down and do self-study. In this case, a class is perfect as it forces you to take out a number of hours in your life just to prep for the gmat
I'm not saying a class is bad, I'm just saying if you're just weak in quant, you might be better off just getting a book and doing some intensive self-study.
There are some books which I think are pretty good for brushing up your basics:
1) Kaplan maths workbook - Touches only on quant subjects tested in gmat.
2) Arco maths workbook - It's thick and really goes back to basics
3) Princeton maths workbook - Same thing as Kaplan. Some people prefers Kaplan's approach, some prefers Princeton's approach. It really depends on the individual.
4)
Manhattan GMAT's guide - Depending on which one you need help on, you can just purchase the strategy guide for that subject, or you can purchase the entire series for quant.
However, if you're keen on a class, then you need to consider whether you want to do it online, or you like a classroom setting. There're a number of gmat prep courses available, so you can really take your pick. So far, I have read in the forum:
1) Veritas - seems pretty good judging by the response
2) Kaplan and Princeton - Been around for ages. Some say they're great, some say they're not so good. Guess it depends on the individual.
3)
Manhattan GMAT - Online course and their guides are highly touted.
4) GMAX Online - Online as well, but last I read, they are coming out with CDs. I also read that you can just purchase the cds that touch on the quant, or just the cds that touch on the verbal section, or the cds for the whole course. Seems to be the least costly of the four I mentioned here.
Meantime, I suggest you visit the maths forum and participate in the discusions. Don't be afraid to ask and don't be afraid to make a mistake. We all make mistakes and the purpose of this club is to help one another learn.