10 childhood games and activities that have become competitive sports

Think back to your childhood, what were some of your favorite playground games?  You could play some of those games competitively as adults today.

1. Hide and Seek
2. Board games
3. Red Rover
4. Nerf Battles
5. Marbles
6. Four Square
7. Speedcubing
8. Musical Chairs
9. Dodgeball
10. Tag