I got my son a CZ-452 "scout" when he was 6 and it's a fine little rifle. I agree with some of the other comments about making things fun with reactive targets. Also a little fixed power 4X scope is a good idea. Shooting iron sights is a great skill and it's how I learned but let's face it - scopes are cool. Let him learn irons later with an 03 Springfield or M1 when he's a bit older!
For reactive targets, I fill soda cans with water and hang them off a board down range by the pull tabs off of tea cup hooks. They really explode at 25-50 yards when you hit them with a 22lr.
When he masters the rim fire, move him up to center fire with an AR-15. I had My son shooting mine at 7. Drill the safety into his head every chance you get and remind him that even though it's fun, being in control of a loaded firearm is a tremendous responsibility.
My son is now 12. He got his hunters safety certificate at 9 and routinely sits in a 2 man blind with me with a .243 or .25-06. We have our own land and I got crop damage permits, so he's tagged does out to about 220 so far. This year however, he has been informed that dad will not be field dressing any more of his kills. If he can pull a trigger, he can work a Buck 110!