NY -- Standard&Poor's CreditWire 12/3/97 -- Standard&Poor's today has assigned its triple-`A' rating to the District of Columbia's $41 million project revenue bonds series 1997 dated Dec. 1, 1997 due June 1, 2027, issued for the Smithsonian Institution. These bonds are scheduled to sell Dec. 17, 1997. The outlook is stable. The rating on the Smithsonian Institution reflects: -- Its role as the "nation's museum" with 28 million visits annually, its nationally prominent collections, its brand name, and its management's ability to leverage these strengths into business and fundraising opportunities; -- A considerable endowment of about $600 million, which provides a substantial cushion relative to pro forma debt and trust expenses; -- A sizable federal appropriation