How to get someone to talk to you alone?

My teacher invented a new game for our class earlier this morning. It's called Gotcha. Each person gets assigned a target which she cannot tell. The mission is to get the target and tell her "Gotcha" without anyone else hearing. The problem is, the target I got is someone I hardly talk to, which means it's going to be really weird if I suddenly go up to her and ask to talk to her alone. I'm not even with her in any projects! Any suggestions? Thanks!