Shorten the length if you can as it will be more comfortable to shoot. You can only harp on form so much before they tune you out and/or get so frustrated they want to quit.

In that case, just let him have fun and keep safety at the forefront. No walking around on the range...wtg for everyone to be done and the range is clear before walking after your arrows.

It's the best guy time my son and I have as it keeps his sister in the house!