Target Test Prep (https://gmat.targettestprep.com) solely focuses on the quantitative section of the GMAT and has some great study guides and homework to work through. I was originally exposed to this company through Forte Foundation’s MBA Launch program. MBA Launch is a program for any woman looking to gain camaraderie through the MBA application process. For a small amount of money you gain insight from top admissions consultants and also support from GMAT experts as well.
Something that Target Test Prep does every week is a Tuesday hour long session on Math concepts. This exposes you to higher level questions you would see on the GMAT related to the topic of the week, such as Roots and Exponents. While I don’t know how to solve every question they present to me, I am able to practice my GMAT quantitative skills and supplement my other study guides and preparation.
Hopefully this last GMAT will be my lucky charm and I will knock it out of the park.