I have registered my puppy at a dog training club.  With all the dogs I've ever owned I only tried a puppy club once and it was chaos. Just went one evening, walked out half way through and never went back.
I've signed on to another one £45 for 8 weeks paid up front.  It says "please bring plenty of small training treats".  I never, ever give treats to any of my dogs.  They have their food and water.
I would be grateful if anyone reading this could advise me what to get.  Maybe take some of her food?

If she gets kibble you could use that, small cubes of cheese or sausage or you could make liver cake (or sardine cake)  Or you can buy stuff from supermarket/p@home

Training  treats should really be something a bit different to the regular food. Small bits of cooked chicken or liver if you want to keep it healthy, cheese or hotdog sausage is good too, although cheese can get a bit squidgy if its a warm hall.
You can also buy training treats from most pet shops.

I never, ever give treats to any of my dogs.  They have their food and water.

Would you work for no pay? Maybe, if you had no choice, or REALLY loved what you did. Would you enjoy it more if you got a really good pay cheque? I bet. Dogs are much the same. :) Forget boring shop bought dog treats and bring a big tub of hot dogs, sausages, cheese, liver, ham, chicken, anything similar  -ideally swap the type every week.