It's okay for kids as young as 4 to take a spin on the ice as long as they're steady walkers and can balance on one foot for more than 15 seconds. If possible, start young skaters on double blades. Skate only on solidly frozen surfaces that have been approved by the local police and recreational departments. (Check for signs around lakes and ponds.) Children should skate in the same direction as the crowd, avoid darting across the ice, and throw away gum or candy to prevent choking in case of falls. Some experts are now urging that skaters 6 and under wear helmets to prevent head injuries.