My character is a student of Winterhold College. Can I leave the weapons I collected as loot and rewards from my quest in my assigned room? Inside the chests? Won't they be stolen while I am away during long quests? Thanks for your replies!

They should be safe. I wouldn't put items in barrels though.

Cupboards and wardrobes should be safe. Not too sure about the chests.

The chests are fine too.

Id be hesitant seeing as how tolfdir and jzargo always skulking around in there and sitting in my chair.

I'm like wtf GtFo my room!!!

Tolfdir is always in my room in his spare time!

Unofficial patch fixed it.

The barrels definitely respawn - don't put anything you want to keep in them.