You can have an English baseball game. Split the class into two teams and set up the room like a baseball diamond. You are the pitcher. Hold up flash cards of Spanish words that they must translate to English or sentences that they must fill in the blank (or they can conjugate verbs, etc.) With each right answer, they get on base or move to the next base. I'm sure you get the picture. If I have any other ideas, I'll post them here later (working on piano lessons right now :-) )