What happened to all the air benders?
Long time ago when Aang first knew that he's the avatar he ran away, he froze'd hem self in an iceberg for a hundred year, in that time the fir nation attacked all the air temples, but Aang wasn't there to Protect them, luckily Monk Gyatso had an Idea: they can hid in a secret cave that only an air bender or a bison can find it, and then go to the spirit world and stay there forever, and the bison's can fly away to and hide there, and if Aang ever comes back and find them, the bison's well tell Aang where are the air benders hiding, and then everyone well live in peace.
The end