Twelve Subjects

[vivamus42]

No: HPFGUIDX 77163

Has anyone identified the twelve subjects making up the 12 possible 
OWLs?   (BTW, how could anyone take that many subjects, yet Percy got 
twelve OWLs?  Even Hermione couldn't do that many with a Time Turner.)

Classes Everyone Takes:

1. Defense Against the Dark Arts
2. Transfiguration
3. Charms
4. Herbology
5. Potions
6. History of Magic
7. Astronomy

Elective Classes:

8. Care of Magical Creatures
9. Divination
10. Arithmancy
11. Muggle Studies
12. The Study of Ancient Runes

I can't find reference to any more than that.  Is that it, or are 
there more?

Vivamus