'Friends' that are theives.

Bake some exlax brownies.

In my experience, exlax doesn't work. I wish it did. But of the times I've tried it, it's just given the person the farts.

Coachs have ways of finding things out as I am sure you already know:) I say let everyone know that it is happening so they watch their stuff and start locking yours up.

They couldn't be blinder. When my wallet was stolen, there were 4 of them in plain sight of it, and none of them saw a thing.
Everyone knows there are thieves, it's just we don't know who. Things get stolen daily, and everyone just says, "Aww, that sucks" Then they tell about all the stuff they've had stolen.
 
The ink stuff in the hands sounds good...if you could find it. And, what if the coach is the one stealing? Perfect cover (apparent 0 tolerance for thieves, he's in charge). And finally in case you can't find anything. Do a survey and find out everybody who has been stolen, and lay an eye on the one(s) who haven't been.
 
I like the ink idea.

Also, most people that steal from their "friends" don't act or look like they would steal. Once you catch the thief, my guess is you are going to be quite shocked on who it is. It could be someone very close to you, someone who you might have just given the stuff to if they asked. People do some odd stuff.

What ever your trap is, don't tell anyone at all about it. I would do the ink, because you could tell right then. Make sure it is something that will stain and is hard to wash off. It won't cause any internal pain or could be hazordous as tainted food could be.

Keep us updated.
 
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