Broadcasters are expected to face a grilling today in Congress over their alleged lackluster compliance with a law requiring TV stations to meet the educational needs of children.Action for Children’s Television founder Peggy Charren will be among the witnesses at the House telecommunications subcommittee session chaired by Rep. Ed Markey. Also testifying will be Shari Lewis and her puppet Lamb Chop, and Jeff Chester, head of the D.C.-based Center for Media Education. Broadcasters will be represented by Paul LaCamera, veepee and station manager at ABC affiliate WCVB-TV, Boston, and Brooke Spectorsky, general manager at WUAB-TV, Cleveland. Congress passed a law in 1990 that places a broadcaster’s license at risk if the TV station does not air educational programs for children. The bill also limits advertising during kidvid hours to 101/2 minutes per hour on weekends and 12 minutes on weekdays. TV watchdog groups have complained that broadcasters are doing as little as possible to meet the law’s mandates. As proof, they cite claims made to the Federal Communications Commission by some broadcasters who have stated that programs such as “G.I. Joe,”"The Flintstones” and “Gilligan’s Island” are sufficiently educational for children. ACT founder Charren believes the Clinton administration is committed to putting teeth in enforcement of the kidvid law. Charren, who met briefly with First Lady Hillary Rodham Clinton yesterday, said it is “inconceivable” the new administration will not actively press broadcasters to do more for children.