“Oh, she got a letter just like that and disappeared off to that—that school—and came home every holiday
with her pockets full of frog-spawn, turning teacups into rats.”
-- Petunia Dursley on her sister Lily (PS4)
Ordinary frogs have several magical uses, but none of them end well for the frogs.
- The actual use of frog parts in Potions is not known. It is noted only because some third years "plastered frog brains all over the ceiling of dungeon five" during October of 1992. (CS8)
- Hagrid used frog liver in Care of Magical Creatures class to feed the baby Blast-Ended Skrewts (GF13).
- Petunia Dursley said that her sister Lily came home from Hogwarts with "pockets full of frog spawn" for some unknown reason (PS4).
Unknown, but frog brains were available to Third Year students.