i have been knapping for a few months and i have noticed a great difference. My bro and I are lucky enough to have a well known knapper down the road from us (been hunting with him for years, should have started a long time ago).I started out using a glove on my left hand, but soon realized that i couldnt feel the ridges that well. I find my rock is red and sticky before i realize i cut myself. kids hands are alot more sensitive than adults (heck im still a pup at 22 myself...lol) but ya might consider starting on glass since its easy to find and cheap if not free. Check out youtube.com they have some great videos. Some of the best come from "scalp creek" he uploads vids on a regular basis. But remember, there is only so much you can learn by watching. Kids are "hands on" learners, let them break a few rocks, get cut-hopefully not too bad, and eventually make a decent point. They will learn more in one hands on session than a weeks worth of videos!