OUTSIDE OF THREE-PUTTING A GREEN, what used to really tee off Casey Golden, 13, was his father's insistence that, when they played golf together, the boy clean up the broken wooden tees discarded by previous players at their club in Evergreen, Colo. "Dad said they'd jam the mower or dull the blades," Casey explains. "I thought, 'Why isn't there a tee that just goes away naturally?' "

Three years ago, as a project for an afterschool class called Creative Analysis, the straight-A student set out to devise such a tee. Last month, Casey Golden's BIO-T—which when moistened melts into an organic brown goo within 36 hours—made its pro debut at the International, a PGA Tour stop in Castle Rock, Colo.

For his invention, Casey drew on ordinary household items and, perhaps, the above-ordinary tolerance of parents who were already raising three older siblings (one early experiment blew a hole in the side of the family microwave). Eventually he baked a mush of flour, water, fertilizer, peat moss, grass seed and applesauce into a dirt-colored tee sturdy enough to support a golf ball and innovative enough to win $1,000 from Invent America, a nationwide contest for K—8 students. "At the finals," says Casey, "there was a bunch of good stuff—this big machine that, like, picked up oil, a skateboard that turned into a bench, and this Oriental kid had an earthquake-proof house. I was surprised I won."

Sensing opportunity, his father, John, an insurance salesman, formed a company to make and distribute Casey's tee. Casey's original formula has been retooled to make the tees less brittle and to assuage greens-keepers, who, fearing their courses would be contaminated with alien grass, asked that seeds be omitted.

The firm has orders for 6 million tees. Even though they will retail at 3 cents each, roughly double the cost of the wooden version, that's hardly a financial hole-in-one. Yet John, 50, has quit his job to sell BIO-Ts full-time; since rain, dew or just plain sweaty hands will trigger the disintegration, Casey and the Goldens figure success is all but guaran-teed.