This time of year, my campus is flooded with prospective students and their parents. The fellows tend toward sports jerseys and cargo shorts, while the ladies favor midriff-revealing tops, skintight jeans and heels.

I am, of course, talking about the dads and moms. As one who remembers a day when men appeared in public in suits and ties and women looked a lot more like Mamie Eisenhower than Kim Kardashian, I’ve watched Americans get younger and younger over the years, and now Matty Simmons’s one-of-a-kind book goes a long way toward telling us how that happened. Simmons was the co-producer with Ivan Reitman of the iconic movie that is the subject of this memoir, which makes him at least partly responsible for the world view that says that life, at its core, is really just one big keg party.

The march backward from staid adulthood to giddy youth began when Little Richard and Elvis invented the teenager, and it’s a commonplace that George Lucas made us all want to be kids again with the “Star Wars” series. What’s been missing up to this point is a close look at the years between, and while Simmons’s book isn’t a coast-to-coast survey of popular culture in the ’70s, it does offer a unique look at the one movie that, more than any other, told Americans it’s okay to access your inner frat boy. In fact, it’s recommended.

Based on the recollections of one of the screenwriters’ days at Dartmouth, “Animal House” is really a training film for those who believe that reality is best faced when, as the subtitle of Simmons’s book says, you’re fat, drunk and stupid. In retrospect, it seems as though hardly anyone in power in 1978 embodied or even vaguely understood the appeal of those virtues. Certainly the executives at Universal Studios were shocked by the script, and director after director passed on it; one, in a colossal understatement, said the film seemed too “rowdy.”

Universities, too, didn’t want to be tarred by the antics of the student body of fictional Faber College. One after the other, they refused to let their campus be the set. Finally, the president of the University of Oregon said yes; several years before, he had been at a California school that had passed on “The Graduate,” and he wasn’t about to let the same mistake happen twice. He did stipulate, though, that his institution never be mentioned in the movie.

The University of Oregon gave them only 30 days, so director John Landis began filming fast and furiously with a cast that included unknowns Kevin Bacon and Karen Allen as well as John Belushi in the unforgettable role of “Bluto” Blutarsky. Before long, Simmons and company had a rough cut to show a test audience. Remember, this was a movie that studio execs were skeptical about, at best; they tried to get the producers to cast old-school comics such as Buddy Hackett and Schecky Greene. “But at the end of the film,” says Simmons, the test audience “literally stood on their seats and screamed. They threw popcorn in the air, they yelled in delight, they hugged each other. We were stunned, all of us.”

As Reitman says, “The one thing about ‘Animal House’ is that it really changed the comedic language. Before ‘Animal House’ they were all watching Bob Hope and Phyllis Diller and Dean Martin and Jerry Lewis.” Some viewers still didn’t get it: One review said the filmmakers should have watched Buster Keaton’s movies and the Pink Panther series.

But the rest of us did. When Bluto peers through a sorority house window as the ladies giggle and romp in their underwear and then turns to the camera and smiles knowingly, he is inviting us to enter a whole new world, one in which the grown-ups aren’t in charge anymore.

These days, if that world often seems a little too juvenile for your taste, bear in mind that “Animal House” stands for everything the Taliban opposes. Toga party, anyone?

Kirby teaches at Florida State University and is the author of “Little Richard: The Birth of Rock ’n’ Roll.”