"Zapped" is a C-grade movie all the way. A descendant of such '60s farces as "The Absent-Minded Professor" and "The Love Bug," it is tempered with some very unfunny steals from "The Exorcist" and "Carrie."

Teen idol Scott ("Happy Days"/"Joanie Loves Chachi") Baio, initially disguised behind oversized glasses and a passive demeanor, is woefully miscast as young genius Barney Springboro, who accidentally ingests a mixture of marijuana and plant food that gives him telekinetic powers.

The movie's ostensible drama revolves around how he will use that power: Good-looking hustler and best pal Willie ("Eight Is Enough"/"Paradise") Aames wants to use it for gambling and betting, while class president and intrepid reporter Felice Schachter wants it channeled into scientific research. Guess who wins?

There are sexual undercurrents, as well: Aames wants to bed curvaceous cheerleader/sex symbol Heather ("The Fall Guy") Thomas, who's going steady with a pre-law student; Baio and Schachter move a little more slowly to the same objective, and the sex-starved principal, Robert ("Soap") Mandan, spends most of the film in nerve-racking anticipation of meeting someone through the classifieds. Even the venerable Scatman Crothers gets into the act as the henpecked baseball coach, so that most of "Zapped's" humor revolves around sexual frustrations or the crazy tricks Baio plays on those who cross him. These consist mostly of popping girls' blouses open in public, making baseballs bounce right for the school team, and easing the ball into the right number on a roulette wheel--pretty tame stuff.

The special effects by Rob Blalack are ludicrous--a model of the Starship Enterprise floats through a fish tank and then circles a dog; a model plane dive bombs its manipulator; two boys who moon Barney get slowly floated onto a tree branch--pants down and behinds to the audience. This sophomoric humor comes to a head in "Zapped's" final scene, the senior prom. It's like the finale of "Carrie" without the tension or reward: after Barney gets hit in the head with a watermelon, his schoolmates laugh at him, triggering a petulant rage that leads to mass blouse popping, dress shredding, un-panting and nudity. It's the stupid climax one has by then come to expect.

Despite an "R" rating dictated by the cheap but abundant nudity, "Zapped" is obviously directed at the 10- to 17-year-old market that thinks all adults are out to lunch (Barney's mom is on Valium, his dad on prune juice; when in doubt, they call in two bumbling priests for an exorcism).

Baio and Aames are harmless, likable actors who are called upon mostly to squint (Baio) and smirk (Aames); Thomas is mostly required to express embarrassment at the frequent exposure of her breasts (though she seems to be the only girl in "Zapped" who wears a bra). None of the "adult" actors, mercilessly buffooned, should bother adding "Zapped" to their list of credits. Ultimately, everyone is upstaged by Schachter, who (even behind thick glasses) displays immense charm and considerable skill--sort of a scaled-down Brooke Shields with acting ability. Were she not in this film, a better title would have been "Sapped."