“Do you remember a single day of high school where you came home and went, ‘Yeah, that was all right?’ ”

Patton Oswalt poses this question but doesn’t wait long for an answer. That’s because he knows – just as anyone who has ever battled acne or performed poorly on the SATs knows – that the answer is no.

“Every single day was, ‘I’m going to (expletive) die.’ Or, ‘I (expletive) rule,’ ” says the comedian and actor. “Or, if anything, the closest you got to ‘That was all right’ was, ‘I’m so (expletive) bored, I’m going to set fire to a police car.’ ”

Oswalt, 42, is sitting in a Washington hotel and waxing philosophical about the intensity of the high school experience – all that Sturm und Drang that accompanied the surging hormones and weird locker smells – because it’s an underlying theme in his new movie, “Young Adult.”

The ultra-dark comedy stars Charlize Theron as an aging “mean girl” who returns to her Michigan hometown to reconnect with an old boyfriend who happens to be happily married.

Oswalt plays her unlikely confidant, Matt Freehauf, a former classmate and fellow heavy drinker who still bears the physical and emotional scars from a brutal high school beating.

Both characters have never fully rinsed off the residue of their high school experiences. And, in a much more positive way, Oswalt still carries a bit of his around with him, too.

That’s because the Sterling, Va., native discovered something important when he was in high school. He realized how funny he was.

“There was a clique of us who were all into comedy,” he says. “I was just the only one that made it into a vocation. I was the only one dumb enough to think I could make money doing this.”

These days, he’s a stand-up comic; the voice of the mouse-chef Remy in Pixar’s “Ratatouille”; a best-selling author; a recent Grammy Awards nominee in the comedy album category; and an actor venturing into increasingly serious, subtle territory.

Actually, Oswalt wasn’t the only person at who recognized his ability to get laughs. Ron Richards, a social studies teacher who had the future comedian in two of his classes, would often crack up with his students as Oswalt re-enacted the morning show routines of former DC 101 shock jock, the Greaseman. Richards knew the kid was going places.

“In between jokes, I looked at him and said, ‘Patton, forget about going to college, man,’ ” Richards recalls of one particular classroom exchange. “ ‘Your future is making people laugh.’ Sure enough, that turned out to be a bit of a prophecy.”

Oswalt did go on to college – he graduated with an English degree from the College of William & Mary in 1991 – but beelined from there to the stand-up circuit, a path that eventually led to TV gigs, including a role as Kevin James’ nerdy friend on the sitcom “The King of Queens.”

Starting with 2009’s “Big Fan,” a portrait of an irrationally obsessed and lonely New York Giants lover, Oswalt has begun to explore more serious, dramatic material on the big screen. For “Young Adult,” he hired an acting coach for the first time.

“I basically just put myself through boot camp, emotional and physical-wise, so that I wouldn’t have to think about that on the set,” the husband and father explains. “So I could be somewhat close to the level of skill that Charlize has, if that makes sense.”

The effort has earned him positive reviews, as well as a Critics’ Choice Awards nomination for best supporting actor. Again, all the accolades aren’t surprising to Richards, who got a glimpse of Oswalt’s acting potential when he coached him on the forensics team.

During Oswalt’s senior year, the self-described movie geek and editor of his high school newspaper interpreted Monty Python’s “The Bookshop” sketch in the humor category. He wound up winning first place in statewide competitions.

It’s an experience that clearly wasn’t forgotten; Richards says his former student has sent a annual check to the debate and forensics team for the past eight years.

Clearly, the guy who once sneaked off campus to see “Wings of Desire” at Georgetown’s now-long-gone Biograph theater still values his own high school experience. But unlike the characters in “Young Adult,” Oswalt’s growth does not appear to have been forever stunted by it.

“What I loved about this script,” he said of “Young Adult,” “is it’s so much about Gen X being dragged into its mid-40s. You’re an adult now. You had your years of youth and hell-raising. That’s fine. But now, it is unseemly of you to keep acting like, yeah, I’m in my cargo shorts and my ironic T-shirt. Really? Because you’re 43. You probably shouldn’t wear that.

“I think before us, people aspired to be adults. That was the aspiration,” he added. “And now, the aspiration has reversed. We want to be kids. Adults want to be kids, which is kind of sad.”

Sad? Maybe. But when described by Patton Oswalt, also pretty (expletive) funny.