Well, I know how frustrating it is to have a puppy with tons of energy and does not take to training very quickly. Adele was a very hyper puppy and also the 2nd dog, so maybe Molly just needs more exercise (even though I'm sure you give her a lot, some dogs are just that way) and more alone time with you? I think I didn't give Adele enough time with just me when she was a puppy, I usually had Marta with me, too, and I think she would have learned what I wanted from her faster if I just had her without any distractions.

Do you think maybe you could do some work at a place that trains dogs in exchange for classes? When I was 12 my family didn't want to pay for me to have piano lessons so I was able to help my teacher with her lessons in exchange for my own lessons. Or maybe you could convince your parents to let you save your own money for classes. Well, anyway, sorry I'm not better help, but I can understand how you feel! Good luck.