No matter what you do, kids will cut themselves. I
demonstrate how to use the knife, particularly in cutting
away from yourself. Basically you want kids to be very
alert, and in control of the knife. Stress that they may
need to pass more than once, because if they "drive" the
knife into the "stuff" too hard, they lose control.
Also, you want to count them when they return them. For some
reason, matt knives/art knives walk.