From San Francisco Public Broadcasting System affiliate KQED comes Chen's guide to children's television. For 20 years the public conception of children and TV has gone hand in hand with words like addiction, exploitation, and plug-in drug. To those who suggest turning it off or throwing it away, Chen (currently director of the KQED Center for Education and Lifelong Learning and formerly with Children's Television Workshop) more realistically responds with a call to control its use. Likening this type of control to watching one's food intake, he prescribes a family TV diet plan, under which children ask to watch a certain program, not just "watch TV." He delves into the use of VCRs, the worth of camcorders, and the dangers of video games. Mr. Rogers is spoken of glowingly, and the oft-maligned Barney comes through with positive stats. Chen praises reading, abhors violence, and talks common sense. A very worthwhile purchase for public libraries.-Linda Beck, Indian Valley P.L., Telford, Pa.