 He designed the Xylopipes xylophone children's toy for Creative Playthings.Rosenbaum created "Light Boxes", kinetic sculptures using polarized light and layers of cellophane laminated between pairs of rotating glass disks, producing changing patterns and colors similar to, and on a smaller scale than, light shows projected at rock concerts in the 1960s.He was exhibited by the Landau Gallery in Beverly Hills, among others.