I've been helping children learn how to cook simple, healthy foods in after school cooking clubs. One thing that crops up is helping children develop skills in using kitchen implements safely and effectively.
One thing I've learnt is that using proper equipment is much safer than equipment that is "for children". A good, sharp kitchen knife is better than a blunt "safer" one as children can cut without straining and pressing hard which is much more likely to lead to slips and cuts. I've found that children seem happier using a knife with a serrated edge as this gives a better grip when cutting.
Having effective ways of explaining something is at the heart of helping people to learn new things. I found "the claw" and "the bridge" good ways to explain how to cut safely. The picture is a great example of "the claw" with the fingers holding the tomato well away from the blade.
"The bridge" involves holding something between thumb and forefinger to make a bridge and the knife cutting down between them.