This may sound like chaos but it’s actually the most fun thing I’ve ever done.
Have teenagers separate into small groups (no more than 5 per group). Put a box full of props in the center of the room and at the count of three let them run and get the first prop they can. This is the one they will have to use. Then, hand each group 10 unfamiliar words (they can be new vocabulary or another language). Now, each group gets a five minute time limit to come up with a skit in which they must use their props and their vocabulary. Have each group present their stuff. No one wins or loses, this is just to establish group work and friendships. Have a blast!