The Moonta Mines Museum occupies the former Model School, built in 1878 for the mining community. Its rooms cover the Cornish families who came for the copper mines: work underground, friendly societies, sport, clothing, death, schooling, and the small domestic details that make the boom feel human.
It is the best indoor stop in Moonta Mines. Go here before or after walking the ruins, and the scattered stone remains outside will make much more sense.