IPhone 5S stolen

My IPhone 5S was stolen in my classroom last Friday. It has a pass code and a Touch ID. It's locked by Bell and I disabled it with my series number. Now I wonder is there any method for thief to make it available again? I'm not sure if it's really a brick for them now, and I'm looking forward to get it back. I think they will give it back to me once they find that it's just a brick to them. Thanks!