Game time! I love games, don't you? Here's a fun one I played with my kids the other day. If they are younger, you will have to show them how to make one penny jump over the other one. My five year old had a hard time understanding where to jump. Just model a few jumps.
1. Put a penny one each of the spaces except 13.
2. Jump one penny over the other and remove from the board.
3. Try to see if you can leave only one penny on the board.