Trudy Corp., based in Norwalk, Ct., and parent company of the children's publisher Soundprints, has formed a joint venture with the Chart Studio, the South African children's book publisher.

The new venture, Studio Mouse LLC, will combine materials from both companies to create new products targeted to the supplemental education, trade and mass market areas. Trudy and Chart Studio will continue to operate their own separate publishing programs in their respective countries. The objective of Studio Mouse is to use the assets of Trudy and Chart Studio to create new multimedia "books plus" products.

Trudy and Chart Studio will each contribute $50,000 to the venture and will hold a 45% stake in Studio Mouse, while the remaining 10% will be held by employees of both companies. Trudy and Chart Studio will also appoint two members each to the Studio Mouse board, although a representative from Chart Studio will break ties.