I remember when I was 6 years old and my brother used to go seek out guys that were 13 to come over and play football against me while he was the 'permanent quarterback.' I didn't know exactly what the age difference was but I was already playing against older guys.
I hate to play the I-live-in-the-country card but it really takes all of the 'pack the kids into the car and run from here to there' out of the equation.