Drop that soccer ball, peewee! This winter, the United States Tennis Association introduced QuickStart, a small-court format that’s the tennis equivalent of T-ball. Kids ages 10 and under are given 23-to-25-inch racquets and foam balls that don’t bounce too high. Games are sometimes played perpendicular to the regular net, using the doubles lines as baselines and a net that’s three inches lower. Private clinics like Dennis Aran’s Champion Tennis Club (1918 First Ave., nr. 99th St.; 212-876-7766) have been using methods like these for years, and the techniques have spread to the Billie Jean King National Tennis Center in Flushing Meadow (718-760-6200) and City-Parks Tennis, the largest free tennis program in the city. From July 2 through August 13, children ages 5 to 16 can show up at one of 37 city parks for twice-weekly lessons and hit-arounds (check locations and times at cityparksfoundation.org). More-competitive types can go to the National Tennis Center from 3 to 5 p.m. on May 17 to try out for one of 50 slots in the Reebok Urban Youth Tennis Academy, which runs for free throughout the summer.