CoachEmUp is correct. This 4th grade team wanted to be in the A division. Keep in mind that the average class size for Lincoln Christian is around 73, which would make them a Class A school. However, when the OSSAA admitted LCS in 2007, part of the criteria was that they play up a class, so they started in the 2A division. When the high school football team won the state title in 2008, they had to move up to 3A.
I believe it was for safety reasons that the school made the rule that all 4th grade teams must start in the AA division until they can prove themselves.