Music is the means Karen Moses uses to bridge the generation gap between members of the Golden Slipper Club of Uptown Home for the Aged and youngsters who attend a weekly program at the Northeast Regional Library at Cottman Avenue and Oakland Street. Moses is the director of recreation and the music therapist at Uptown. Each Thursday morning from 10:30 to 11, she and a contingent of senior citizens visit the library to put on an intergenerational program for their young audience. They take along musical instruments for the children to play, and they keep their voices in tune during sing-alongs with the youngsters, which Moses leads with her guitar. After the last notes are sung and played, some of the children like to help Moses pack up the instruments for the trip back to Uptown on Bustleton Avenue. The eight-week program will continue for about four more weeks.