Left pocket:
School ID cards (for freshman and sophomore years so far), chap-stick (which I've had for... 4 years? never really used it), house key, sometimes junk that I'll throw away after a few months.
Right pocket:
Random bits of money I forgot to put in my wallet, a thumb drive that doesn't seem to work any more, mechanical pencil, pen, rubbish that I might discard in a month or two, and some random beads I randomly acquired in 8th grade for whatever reason.
Back pockets:
typically unused, since I don't like sitting on my cargo.
Winter Coat pockets:
I'll sometimes but my gloves into these, but then the pockets get kind of... in the way... so I store my gloves in my back pack with the binders, folders, paper, and apparently shredded school planner that got soaked during the second of October 2014.
Minecraft University jacket pockets:
Except for a few grains of sand, likely from Long Beach in Washington state, which some how got lodged in there during my last vacation up there in 2013, I don't really keep anything in them.