First of all, im a fast learner and I take what I do seriously. Meaning, when I started my karate around 4-5 months ago, I would come 5 times and also train the other 2 days at home or at the park. When we didn't do a few of the stretches i would do them at home. Anyhow, after a while until now, I progressed much faster than most others in my group, being the beginner/intermediate class as im a yellow belt 8th kyu(skipped 1st yellow at 9th). What angers me is that there are both adults and kids at our classes, and most of the kids are not doing it by choice and could care less, so they come about 1-2 times a week, and so do some of the adults. Because of these individuals my training is left behind tremendously. We do partner work and kumite, as well as practice Katas together, and I was doing better than some of the green belts, and at my dojo green is right before brown, which is before black. There is nothing more I can learn with some of the class(not all) being so behind. Since I train in the headquarters[where the grandmaster (also founder of the art]resides, there is an offer to train with Soke for an hour class and i've to pay somewhere around 50$ which is too much. What can I do?