I also like the .243 but...
I started out one of my sons on a light .243 and he did very well with it.
For my daughters and my other son, I went with the .308 on a Browning Safari.
I had them use the Remington Reduced recoil loads. This is a much lighter recoil than the .243 I own but the killing power is better. At ranges of up to 150 yards I could not tell a difference between the reduced loads and the .308 full power or 30/06 full power with 165 grain.
These were shots on mule and whitetail deer.
For a young shooter I very highly recommend the reduced loads.
Hunt to Live - Live to Hunt