The children in Mrs. Kernis' fourth-grade class at Bustleton Elementary didn't know it in the '70s, but they were in the company of genius, performing their little skits: fake celebrity interviews, mock awards shows.

"They'd dress up as John Travolta or Elton John," said Bustleton alumnus Adam Mazer, 43, who penned kiddie ditties for fun in fifth and sixth grade, too. "I've always enjoyed writing."

If a man chooses not to put away childish things, he must learn how to convert them to the grown-up world. And Mazer is doing a fine job at that.

There's nothing fake about the Emmy he won Sunday night for outstanding writing for a mini-series, movie, or dramatic special, for You Don't Know Jack, just his second movie. The HBO biopic traced the exploits of Jack Kevorkian, the obsessive Detroit pathologist who became a public spectacle as he helped gravely ill patients kill themselves.

People from the Bonner Street neighborhood, nestled between Bustleton Avenue and Roosevelt Boulevard in the Far Northeast, don't remember a writer, but they do remember Mazer.

"You could just tell that Adam was the kind of person who was going to go somewhere and do something," said Ken Glathorn, his George Washington High School history teacher and sponsor of the Class of 1985. Mazer was class vice president.

"Being a teacher for 35 years, you get a pretty good sense of the students you have," Glathorn said. "Adam was a rock, and you knew that if this is what he wanted to do, he was going to do it."

Though Mazer said he had been interested in writing most of his life, neighbors remember him best as an athlete. "He was a heck of a baseball player," said Mark Miller, one of Mazer's father's good friends.

"Back then, he loved sports," said Mazer's father, Len, who lives in Smithville, N.J., north of Atlantic City. "He loved the Phillies and loved Mike Schmidt. His friends called him 'Schmitty.' "

Mazer said he was on the junior varsity team at George Washington when he got his driver's license at 16. "Once I started driving, I thought to myself, 'Do I really want to go to practice?' Looking back, I do regret it."

Mazer's sister, Randi Kelman, who lives in Kennett Square, said his interest in screenwriting blossomed at Syracuse University, which he attended after George Washington.

"People's memories are different," she said, "but we all remember Bonner Street. It was very close-knit, and many of our neighbors have kept in touch."

As if to prove that, Josepha Gayer, whose children grew up with the Mazers in the '60s and '70s, sent an e-mail: "We are all very proud of his accomplishment as a writer."

He displayed a touch of it Sunday with one of the most quoted acceptance-speech quips of the night:

"Jack Kevorkian, I'm so grateful you're my friend, but I'm even more grateful you're not my physician."

You Don't Know Jack appeared on HBO in the spring and will be out on DVD Oct. 26, featuring an all-star cast: Susan Sarandon, Brenda Vaccaro, John Goodman, and Ramblin' Al Pacino, who gave the Emmys' longest and least coherent acceptance speech for winning the award for outstanding lead actor in a mini-series or movie.

"He's a terrific guy, no ego whatsoever, so gracious," Mazer said on the phone from Los Angeles, where he lives. "I really had no idea what to expect. I was so overwhelmed when we first heard that he was going to play Kevorkian, the legend that he is."

TV writers get a lot more respect and have much more influence on the final product than do feature-film writers.

"I was on the set about three-quarters of the time," Mazer said. "There were a lot of me-and-Al moments . . . talking to me about Jack and what did I know and what did I think."

It's not that Mazer is a beginner in the Hollywood movie game, even if Jack is only the second major film carrying his writing credit. "I sold my first script in 1995, and have sold quite a few," he said. "Some got close to happening. I've been happy to make a living as a writer."

There is a sizable cohort of comfortable screenwriters who have never had one of their works produced. "People outside of Hollywood don't understand how things work," Mazer said. "I do make a nice living."

"I'm happy that it didn't happen too soon. I got to learn what the drive was, how you have to persevere. . . . The last week, last couple of days, I can really appreciate it."

Breach (2007), a spy flick starring Chris Cooper and Ryan Phillippe, was Mazer's first produced feature. He was credited as a cowriter on the film, which Inquirer movie critic Carrie Rickey called "a riveting true-life thriller."

Looking for more riveting true life, You Don't Know Jack executive producer Steve Lee Jones, who owned the rights to Kevorkian's story, went to Mazer. They sold the project to HBO, which hired big-shot Barry Levinson, a longtime Pacino friend and colleague, to direct, and the rest is Emmy history.

In his acceptance speech, Mazer also invoked the spirit of his mother, Sheila, who owned and operated Crossroads Cleaners at Broad and Callowhill and died of cancer in her 50s in 1998: "I know you're with me right here, right now. This is for you. This is for us."

Neighbors, family members, and Glathorn all said they were touched by the moment.

"From her diagnosis to her passing, it was a year and a half," Mazer said. "I put my career on hold - I'd do that in a heartbeat. . . . To be able to say goodbye, to be there in a dignified way, that beautiful experience [in an ironic way] stayed with me." He said it had a big influence on his writing of the Kevorkian movie.

On Saturday, "Schmitty" celebrated the 11th anniversary of his wedding to the former Allyson Schwartz, a child of Bucks County but no relation to the Pennsylvania congresswoman with the same name. Sunday was the Emmy.

On Wednesday, the forever Phillies fan took his children, Jonah, 8, and Ella, 5, to Dodger Stadium to watch the visiting Phils. In the third inning, he caught a foul ball, his first in nearly 40 years of regular major-league attendance, off the bat of Jimmy Rollins.

"It has been a crazy few days," said the Emmy-winner.

Contact TV critic Jonathan Storm at 215-854-5618 or jstorm@phillynews.com. Read his blog, "Eye of the Storm," at http://www.philly.com/philly/blogs/storm/