Certainly a .22 rimfire has its place in marksmanship training since the more we can shoot, the better we will shoot when the fundamentals of marksmanship are adhered to. The affordability of rimfire ammo means that much more shooting can be done than could be with centerfire ammunition alone, but a handloader can make almost any centerfire round manageable for a youngster.
Shooting a .223 or a light loaded .30/06 for that matter, will quickly dispel the novice's apprehensiveness about shooting a physically larger round, which if left to fester could become difficult to overcome if the kid is always told he's not ready for the big gun, or worse, allowed to shoot a heavy kicking gun that hurts him. If you were one of those kids that was passed a long stocked, 6 pound 12 ga single-shot, with a plastic butt plate, that was loaded with an ounce and seven-eighths 3" magnum, lets agree not continue that unfortunate tradition. Even better is a forend that separates from the gun in recoil, and an action that drops open each time it fires. Perhaps that's the gun that should be reserved for cocky teenagers, but its probably better just to let the tradition die.
Its a lucky youngster who is able to shoot both rimfire and appropriately loaded and fitted centerfire rifles and handguns with the family. The advantages of the adjustable stocks and chassis as shown by Todbartell are self evident, otherwise the stock will have to be cut to fit the youngsters, then either lengthened or replaced as they grow. Another habit that needs to disappear is the idea that you give a kid some piece of junk that won't shoot, the old, "AHH its good enough for a kid!". Well if it doesn't shoot for you, what is the kid going to learn from it? In a word, discouragement. Give them a chance, and let them shoot something good.
Lots of kids are allowed to start with semi-auto rimfires. While there are those who will disagree, I don't think this is the best way to teach fundamentals, unless the rifle is treated as a single shot during the initial phase of training. Another reason is that I think there is a significant benefit to the rimfire rifle and the centerfire rifle being similar in the way they work. For example a CZ 452, or one of the later models, combined with a CZ 527, and a CZ 550. Each of these rifles are available with irons sights and are easily scoped, which provides a novice with exposure to both.
