For an adult player to succeed at tennis, racquet control is essential. The same is true for kids. However, since kids are smaller than adults, kids have trouble controlling full-size racquets. They are too long, too heavy and the grips are too large. Kids need racquets that are proportionate in length and weight and have a grip that fits their smaller hands. For 8-and-under, the racquet should be 19", 21" or 23". For 10-and-under, the racquet should be 23" or 25".