For children on school trips or traveling with their families, here is kid-friendly information about popular monuments, museums, exhibits, shopping, sporting events--and even day trips outside the immediate metropolitan area.      Originally published in 1989, this handy guide now features completely updated text and photographs, along with the puzzles, games, and wonderful tidbits of trivia that have made it one of the most useful D.C. guidebooks for children. A Kid's Guide to Washington, D.C. is the perfect traveling companion for any youngster who wants to play an active role in planning a family vacation.   Includes: Puzzles Games Trivia And More!