I wrote a piece once on this subject. Besides the bolt or other manually-worked action for safety and marksmanship, I recommended a low-power scope instead of iron sights.
Iron sights are hard to learn and hard to shoot, making for a discouraging and frustrating experience for a new shooter. Bad.
The average rifle shooter today will use a scope for 99.99% of ALL his shooting. Iron sights aren't even installed on most rifles, and are considered as emergency backups on rifles that do have them.
Scopes are instinctive, even for a kid. Put the cross on the target and squeeze. One focal plane and nothing to align even before you sight on the target.
Go with the instinctive, simple sight system that he'll use for the rest of his life. Get him a decent 4X scope.
