ORIGINAL: nchawkeye
I wouldn't start a 12 year old with deer hunting...Start him out with a .22 and squirrels...Teach him to shoot and to hunt...I see too many middle aged guys deer hunting that never learned the basics of hunting and shooting...I have also seen alot of kids kill a few deer and then give up hunting....They never learn to appreciate nature and the peacefullness of being outdoors.
As far as hunting goes you can start any where you want to. It's the teaching that counts. If you are a good teacher/hunter than your kid will be a good hunter. My father introduce me to hunting at age 12 too. I shot my first deer at that age too, with a 12 ga. I can still remember it like it was yesterday. That is the best feeling I ever had.
What caliber would you suggest to start a 12 year off on?
I started with a 12 gauge for deer hunting, but if you are looking in rifles than, I would recommend 308 or 7mm-08 or if you want to go small than 223 and 243. Almost any caliber up to 30-06 will be good. I wasn't that big of a kid at age 12(4'6, 105lbs) and I was handling 30-06 and 12 ga. Practice, practice is what makes you a good hunter.