Homespun Science Center

`NO one flunks a museum,'' Frank Oppenheimer once wrote. As founder of the Exploratorium, he wanted an atmosphere that provided only a minimum of structure and intimidation - and a maximum of exposure to the phenomenon of science. The result, 20 years later, is a down-home, hands-on kind of place, with little of the sophistication sometimes associated with other successful science museums.

Housed in a cavernous, hangar-like building near Golden Gate Bridge - built in 1915 for the Panama-Pacific Exhibition, and now part of the Palace of Fine Arts - it houses exhibits ranging from an echo tube and a miniature tornado to a cut-away steam engine and a table for dissecting cow's eyes. Eclectic and energetic, the museum is, as one of the founder's colleagues noted, ``like the inside of Frank Oppenheimer's brain.''

Not surprisingly, some of its 600-plus exhibits look more like contraptions found in a basement than objects crafted for display. Slightly dusty, moderately noisy, the museum enforces only one rule: no bike riding. Everything else - including touching, poking, and squeezing the exhibits - seems to be allowed.

Yet the museum has proved its worth. With a budget of $7.9 million and a staff of some 200, it attracts a half-million visitors a year.

And it continues to spin off clones. Museum staff from around the world now come here to study, and the Exploratorium model - complete with the Explainer Program - has been replicated in New York, France, Venezuela, and elsewhere.

The museum is currently re-creating 65 of its exhibits for a Japanese traveling exhibition, which opens June 17 in Tokyo.