Actor and comedian Dave Chappelle holds up the Emmy he won for a monologue on “Saturday Night Live” while talking to students at his alma mater, the Duke Ellington School of the Arts, in Northwest Washington. (Jahi Chikwendiu/The Washington Post)

There are probably few doors in Washington that wouldn’t be open to Dave Chappelle, but D.C. Mayor Muriel E. Bowser presented him with a key to the city on Friday just in case.

In an afternoon ceremony at Duke Ellington School of the Arts, from which the 44-year-old Chappelle graduated in 1991, Bowser paid tribute to the comedian, actor and third-generation Washingtonian.

“He is a man who has made, already in his young life, lasting contributions to our cultural heritage and to humanity,” Bowser (D) said. “Dave loves Washington, D.C., and we love him right back.”

It was indeed a mutual love fest in the packed Duke Ellington Theatre, the shining multimedia jewel of the school that just reopened its Northwest Washington location following a $178 million remodeling. The students roared when Chappelle walked onstage to accept his award.

But this was not showtime and the entertainer was not there to entertain. The first thing the stand-up comic did was pull up a stool and sit down. And for the next 15 minutes, Chappelle delivered something closer to a commencement address than a comedy routine: words of wisdom from a been-there-done-that success story.

“When I look at you, I really do see myself,” he said to the students who sat at rapt attention. “I have kids your age and I tell them, ‘Yo, you don’t have to be awake all the time. But at least three or four times in your life, just pay attention.’ I tell my son, ‘Look around this beautiful house. Everything in this house we’re enjoying is based on decisions I made when I was younger than you.’

“Right now, you guys are making your future. This is a very important time in your life.”

Chappelle told the students that while he never went to college, attending Duke Ellington left him “wildly prepared” for the hard work his career would require.

“When we went to school from 8:30 to 5, I’m not going to lie to you, I hated school,” he said. “I didn’t understand what was happening, but years later when I had my own television show and I was working 16-hour days, it felt easy for me because I had school days longer than that. At least on the television show, I was the boss. Here I had to do what everybody told me to do.”

He urged the students to recognize the hard work and dedication of their teachers, and to “take a moment at some point in your life and thank them because we spend so many hours at this school, they are almost like surrogate parents to us.”

And he noted how the vastly improved school building was an investment in the students that they should see as the city’s belief in them.

“When I walked in this building today, it’s clear to me that you guys, I hope you never take this for granted,” he said. “$170 million is a lot of money. That’s what they spent on you guys, on your future. And the money symbolizes a very rare opportunity to cultivate the talent that God gave you. And I hope that you take advantage of that.”

Chappelle didn’t leave the stage before offering a gift of his own — the Emmy he won earlier this month for the monologue he delivered on “Saturday Night Live” days after the presidential election last November. The gift came with more sage advice.

“This is a trophy, but it represents years of hard work,” Chappelle said. “In the course of a career, you go through so many things. You learn on the job. You embarrass yourself. You fall down. You get up. You try harder. I quit my show and people said I’d never work again. I got up and tried harder. I still do my art almost every day. I still think about my art every day. I want you guys to have this just so you know that even though the odds are wildly against you, this can happen for you.”

Following the ceremony, Chappelle, who has been in town for the past two weeks for a series of shows at the Warner Theatre, visited the school’s spacious lobby where students had prepared a series of short performances, including a ballet, a jazz piece and a dramatic telling of Edgar Allan Poe’s “Romance.”

“He looked very engaged,” said Sky Stringer, a junior who took part in the “Romance” piece. “I was relaxed because he seems like someone who can still relate.”

Peggy Cooper Cafritz, one of Ellington’s founders, was also on hand and spoke about Chappelle’s involvement with the school as evidence of its mission.

“We also teach our kids to be good citizens, to give back, to never forget where they came from,” she said. “It is what Ellington is in a way every day.”