In total, there are 6 different Hogwarts Moment sets - Divination Class, Defense Class, Potions Class, Transfiguration Class, Charms Class, and Herbology Class. But if you're interested in Charms Class, you need to act soon, as it's retiring at the end of 2022. Alas, Herbology Class is already retired and would set you back about $50 if you wanted to buy it from a reseller.