token economy- operant conditioning procedure in which people earn a token for exhibiting a desired behavior and can later exchange the tokens for treats.
I heard of an experiment where the experimenters tried to teach the concept of money to Capuchin monkeys using a food dispenser triggered by the insertion of metal discs. They not only demonstrated economic behavior typical of humans, but also stole, attempted counterfeiting, and independently invented prostitution. You can read about it here.