If charms isn't up your ally I would try Defence Against the Dark Arts. The first couple of lesson's are similar to charms in that you learn the basics to spell casting and the spell categories and types. Lesson 4 is where the two subjects differ. DADA goes into dangerous beasts and how to look out for and defend against them, with more dangerous spells then charms. 
I would be prepared for long wait times on getting your assignments back as  DADA is one of the more popular subjects and the PA's might not all be active and a bit slow.
Some spells you learn are the Knockback jinx and the Verdimillious charm. Some of the beast discussed are hag's, imps and doxies.