Might not be a question for this forum but here goes.

Does anyone know if there is any rule as to whether or not a current student can join the football team this late in the season?

There are no rules about this in the rulebook. I'm sure this depends entirely upon your state or local (probably state) eligibility rules.

I do know that I moved in 7th grade to a new school, and was allowed to join the football and baseball teams mid-year. But that was here, and that was long ago. Check with your high-school first - they should know what local eligibility rules apply.

As far as I know, most schools allow a student who has been there since the beginning of the year to join at any time. Players get hurt and roster spots open up. You may be asking about what happens when a student transfers to a new school in mid year.

Each school district has different rules on this. For instance, some allow it if he was not playing football at his previous school when he transferred to the new school. Others allow it if he moves in from out of state, no matter what the circumstances but have different rules for in state moves.

The purpose of all these rules is to prevent coaches from recruiting and players from moving for the sole purpose of playing football. If the move came from a parent's job transfer, chances are there will be no problem. If it appears that the player is gaming the system in order to play football, expect problems when he suits up.