Bet you can't. This game can be played in millions and millions of different ways, and essentially it's just this: go to the toy store and buy toy money. Give each student the same amount of money at the start. Have the students bet each other that they can't do something - like this: make each S stand up and walk around. Have them say, "I bet you can't (e.g. count to 20, run around the room 5 times, sing the ABC song. etc.)". Get the Ss to bet using the toy money. You'd be surprised how much even adult students enjoy this game.
Can You Actions. Use this game for teaching "Can you...?" "Yes, I can" "No, I can't". These actions are fun: wiggle, dance, run quickly, hop, skip, do a star jump, do a handstand, touch your toes, cross your eyes, snap your fingers, whistle, sing. E.g. Ask a S "Can you cross your eyes?". If the S replies "Yes, I can" then say "Ok, go!" and the S does the action. If the S says "No, I can't" say "Too bad. Ok, can you (wiggle)?".
Can / Can't Lesson Plan. We also have a FREE lesson plan on using can & can't which includes games and activities as well as other lesson materials.