These are milk caps from our glass bottled milk. Maeve traced a small spice lid onto scrap booking paper, cut the circles out and glued them to the milk lids. When the glue dried we numbered them 5, 10, 15, etc. I mostly cared about getting to 60 (prep for learning time), but we had enough to get to 75.
I think these lids would be fun to use as play coins or for a Plinko type thing with a peg board.