They Put Best Foot Forward : Rehabilitation: Inmates from county probation camps are rewarded with a chance to attend the prom they missed in high school.

Authorities threw a different kind of book--Emily Post--at some young lawbreakers when 39 car thieves, drug dealers and gang members got a chance to attend the prom they missed in high school.

After weeks of learning to cut meat with a knife and being told it’s not proper to talk about gangs at dinner, inmates from county probation camps put on donated gowns and military-style uniforms Wednesday and danced until their feet hurt at the Desert Inn in Lancaster.

“This is all part of the goal of showing the kids an alternative lifestyle,” said Barry Nidorf, the chief probation officer for the Los Angeles County Probation Department, which sponsored the event to demonstrate to the delinquents the rewards of a law-abiding life.

Nidorf stood happily among the 20 couples--a boy barred at the last minute for disciplinary reasons was replaced by a staff member--and observed that although his staff is encouraged to come up with unusual rehabilitation approaches, “When I heard about this one, I couldn’t believe they could pull it off.”

But pull it off they did. The only apparent differences from any other prom on any other warm night were the tattoos that peeked out of some of the gowns.

The dance was the inspiration of Michelle Guyman, a deputy probation officer at the Challenger Memorial Youth Center Camp in Lancaster, which houses 550 inmates from ages 12 to 18.

Participation was based upon merit and good behavior. Among the 20 girls chosen was 17-year-old Stella Reyes, a willowy, dark-haired dorm captain. She became a runaway and then ran with gangs. Her nickname, Shy Girl, is tattooed on her upper back.

The boys came from Camp Munz, a military-style facility that uses tough discipline to teach a new code of behavior.

Originally, the boys were going to pick girl partners, but they were so shy that the girls took charge. Stella picked Robert Estrada, a slender 17-year-old with a crooked, ingenuous smile.

“He’s real gentle,” Stella said of her choice. “He talks positive stuff.”

Like Stella, Robert was in for auto theft. He had been in jail before, for burglary and carrying a concealed weapon.

There were instructions on how to eat, converse, walk, since many had almost no training in manners. The girls were told how to stand and the boys were shown how to pull out their partner’s chair.

While this variation on “Pygmalion” was under way, Guyman helped round up donors of $4,000 worth of clothes, flowers, limousines and cakes. The Cal State Long Beach ROTC sent green military uniforms to wear with tux-style bow ties.

On Wednesday, the girls were taken to a camp building, where they helped each other with makeup, hair and clothes.

Deputy Probation Officer Stacy Thompson conducted a class on the correct way to walk, leading a line of girls from one side of the room to the other, her hips swaying slightly.

“Put your head up more,” she commanded. “Don’t chew your gum. One foot in front of the other--natural, natural.”

Like awkward goslings, the girls tried to follow, though several swayed more like tightrope walkers than femme fatales.

“The boys are in the gym,” announced Probation Officer Kimberly Thompson, setting off squeaks of excitement and anxiety. “Do not be nervous. We have worked on this a long time.”

As the boys marched up, in close-cropped haircuts that are the mark of their military-style dorm, probation executive Jan Aven shook her head in wonder. “Several months ago, these kids were on the street, gang-banging.”

The girls took the arms of their escorts and crowded into the limousines for the ride to the hotel, where a Santa Monica band named E.Z. provided music.

Nidorf took the microphone. “When you have a challenge you think is not possible to achieve, remember tonight,” Nidorf told the inmates.

Then it was Stella’s turn. “Tonight we feel more cared for, more loved, and more human,” she said simply, receiving a standing ovation.

At the top of Robert Estrada’s list of what he wanted to achieve was to see Stella again.

It wouldn’t be easy. They couldn’t make a date. He sat by himself trying to figure out if she would agree to see him after they both finished their sentences.

Discarded high heels--the first that some of the girls had ever worn--were piling up as a dance contest wound down.

“I don’t want it to be over,” Stella said.

But just like Cinderella’s coach turned into a pumpkin, white institutional vans rolled up to replace the limousines, and it was over.