I've been using these coupons in my classroom for two months now and the kids really love them. We use Class Dojo and the kids get paid every Friday for the points that they have earned that week. Then we open the Dojo Store. The kids do it all, so it isn't a pain for me at all and they have to use a little math in the process. I have two bankers in my classroom that handle pay day and selling everything. 

All the rewards are free with the exception of pencils. I buy pencils from Target when I find them in the dollar section. I haven't run out yet. Head on over to TPT and grab them!