Prince George's County officials last week handed over the keys for a shiny car to a recent Laurel High School graduate as her reward for partying until dawn on graduation night, dancing until her feet hurt and staying drug- and alcohol-free.

County Executive Parris Glendening Friday presented the 1983 Plymouth Reliant to Stephanie Thomas, 17, as part of a county goal to attract more students to school-sponsored drug- and alcohol-free parties.

Thomas won the car as part of a number of door prizes given away at Laurel High School's June 4 celebration for its graduating seniors.

Legislation passed by the County Council provides that Laurel be given one car each year to use as a door prize during its graduation party.

The cars are taken from the large arsenal of vehicles seized by county police during drug raids. Under the new law, a car will be set aside each spring from those slated for the auction block and given to the school board.

Laurel officials are already calling the program a success. Of the 320 Laurel graduates, more than 290 attended the all-night celebration.

The party, which lasted until 6 a.m., also included such door prizes as radios, videocassette recorders and computers donated by parents and community residents.

"The whole event was about having fun the old-fashioned way, where you remember it the next day," said Tom Kirby, Laurel's principal.

Thomas, who plans to attend Rutgers University in the fall to study environmental journalism, said she believes that students will understand the sentiment behind the graduation-night festivities but that the message to drug users and pushers is even more meaningful.

"Obviously, dealing drugs doesn't pay, because the dealer whose car this was won't be getting it back," said Thomas, reclining in the car's plush blue velvet seat.

Thomas, though, will spend her first year at Rutgers without her newest possession. Rutgers has a school policy prohibiting freshmen from bringing cars to the campus.

The legislation giving Laurel a car was sponsored by council member Frank P. Casula, who represents the Laurel area. Although the new law provides for a car to be given to Laurel only, the council is expected to consider legislation in the fall to expand the program countywide.

Another county school, Frederick Douglass Senior High in Upper Marlboro, purchased a car this spring and used it as a door prize for graduates.

Glendening said he hopes the prospect of getting a free car or other prizes deterred many seniors at Laurel from spending graduation night drinking and driving and perhaps becoming alcohol-related death statistics.

"This program sprouted from concern for youths about what is unfortunately the reality . . . dozens of young kids killed at what should be the highlight of their lives," said Glendening. "Who knows how many lives this program has saved and will save."