Here's a little info on the 7mm-08 Recoil.
120 grain bullet at 3000 FPS,Rifle weight 7.5 lbs...Recoil Energy 12.1....Recoil velocity 10.2
140 grain bullet at 2860 FPS,Rifle weight 8.0 lbs.....Recoil Energy 12.6....Recoil velocity 10.1
For more info of other calibers check the link I used.
www.chuckhawks.com
I bought a new Savage 7mm-08 last Fall for Deer Season and it did a great job on a nice Big Doe opening morning and a 8-Point Buck the following friday...would have been a 9-Pointer but he had a broken brow-tine....recoil wasn't too bad on the 7mm-08 and if a Person was to use the Remington "Managed Recoil" shells the recoil would be even less for a Youth!
You can compare the recoil of the 7mm-08 to other calibers to give You an idea of what to expect and what calibers would be easier/lighter on a Youth.
Here's an example of another Caliber Rifle with more felt recoil:
30-06 Springfield 150 grain @ 2910 FPS...Rifle Weight 8.0 lb.....17.6 felt recoil energy....and 11.9 Recoil Velocity