Guards come in various sizes.
Buy a guard that covers the front of the leg from 2-3 inches above the foot to a height equal to the top of the calf. The shinguard should conform to the shape of your child's leg. When a shinguard is strapped in place, look for good contact with the leg. You'll want shinguards that are easy to wash, either by hand or by machine. Look for a guard with a lining that's been treated with an antimicrobial agent to reduce odor .