stay in the locker room naked for 1 hour, just walking around. try to keep a boner.

Next time you go to a locker room, before you leave, leave your underware in the locker room, then go commando for 3 days. Then if they are still there you can stop going commando. If they aren't, you must sit naked for 5 minutes while someone else is in there. You can't be in the shower, you must be in the center while someone else is there. If someone leaves/the center part is empty and there isn't someone who sees you, you restart.

(And just for the heck of it I'll do the next 3 below. The person above will do them, and I will do them as well)

Shower with your clothes on before you leave

Piss on yourself.

Wear oppisite sex underwear and change in plain sight for all to see....

Shave your crotch in the shower without hiding from anyone coming in

How about a school approprient one.....

ok school appropriate
go commando for class

lock all clothes/towel in locker so you have no items to cover yourself and then drop key in trash / drain
Shower then pretend someone stole you key and ask everyone in locker room even go to reception desk naked and ask for help

Use the hairdryer on your crotch area for 5 minutes

When you take a shower at the locker room, don't take your underwear off. Shower with them on.

For me, I'd prefer if the dare wasn't extremely public (I don't want to talk to people, or run around the room, or do something that would make me really stand out)

(Dare_Master.. that's alright. Normally it wouldn't be, but these showers are private!)

stand naked in the shower for five mins (cover your self if needed but you have to be naked) then you can shower

hope its alright

While you are showering, make sure at least one other guy is present and give at least 3 nice heavy moans of pleasure. You can be doing whatever you want in the shower while you do it.

Cum into a random locker and leave it open afterwards so people can admire your handiwork

Wair a jockstrap to school / public changing room and sit in it for 5 mins

nothing to extreme, I only want original dares