My former boss has sent me the tutoring materials we used years ago. Is there a standard licensing agreement for this kind of thing, like I pay him $2 for every time it’s reprinted?
The “licensing agreement” consists of whatever payment the two parties work out between themselves.
You haven’t given us a whole lot of information to go on here. For example, what are you planning to do with the materials he sent you? Use them for tutoring a few students? Open a bookstore and sell the materials?
Assuming your former boss is the copyright owner, and you are using/printing the materials with his permission, he is free to charge as much or as little as he chooses, including no charge.
You, on the other hand are free to pay what he asks, or decline to use the materials, or make a counteroffer.