"Monsters University" easily graduated at the top of the box-office class this weekend — even as "World War Z" finished with a better-than-expected grade.

Pixar's 3-D animated film starring a bunch of furry creatures was No. 1 with a stellar debut of $82 million, according to an estimate from distributor Walt Disney Studios. While the prequel to 2001's "Monsters Inc." met industry projections, "World War Z" exceeded them. Heading into the weekend, the Brad Pitt action thriller was expected to open with no more than $55 million. Instead, the pricey Paramount Pictures' production took in a healthy $66 million during its first three days of release.

Pre-release audience surveys also suggested that "World War Z" would trail "Man of Steel," which has now been in theaters for two weekends. Instead, the Superman film saw its ticket sales tumble 65% to $41.2 million — leaving the superhero to settle for third place.

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Since its first release in 1995, Pixar has seen every one of its 14 films debut at No. 1. “Monsters University” marks the second-highest opening ever for the Northern California-based company, behind the $110.3-million launch of “Toy Story 3” in 2010.

“Monsters University” follows a young creature voiced by Billy Crystal who heads off to college to learn to be a professional scarer. The movie received mostly positive reviews and was well liked by audiences this weekend as well, who assigned the film an average grade of A, according to market research firm CinemaScore. The film appealed to a slightly more female crowd, and 60% of opening-weekend moviegoers were under the age of 25.

The movie did particularly well with Latino audiences, doing above-average business in places such as El Paso and Brownsville in Texas as well as Albuquerque.

“Traditionally, our family films have played great to Hispanic audiences, but I’m going to guess we’ll be even stronger with that demographic on this film,” said Dave Hollis, Disney’s executive vice president of distribution. “We have an appreciation of the changing marketplace for moviegoers and made a dedicated effort to marketing to that audience.”

Upon its release in 2001, “Monsters Inc.” became a huge hit, launching with $62.6 million and ultimately grossing $562.8 million worldwide, not adjusting for inflation. The latest “Monsters” film is on track to meet that global tally, having collected $54.5 million from 35 foreign markets including Russia and Brazil over the weekend.

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Meanwhile, many in Hollywood had forecast doom for “World War Z,” after the $200-million-plus film was plagued by numerous troubles, including extensive rewrites. The film, based on a novel by Max Brooks, stars Pitt as a U.N. investigator trying to save both his family and the world from a zombie apocalypse. The picture, directed by Marc Forster, was co-financed by Paramount, Skydance Productions and GK Films.

The surprisingly strong opening is good news for Pitt, whose production company Plan B Entertainment is behind the movie. “World War Z” is now the 49-year-old actor’s biggest opening by far, followed by the $50.3-million debut of 2005’s “Mr. and Mrs. Smith,” on which he fell for his costar and now romantic partner Angelina Jolie. In recent years, Pitt has focused on a number of smaller, art house-aimed pictures, such as “Killing Them Softly” and “Tree of Life.”

“I think the fact that Brad Pitt promoted this so heavily and was willing to stand in front of it was a lot of why people were like, ‘Oh, this movie must be working. He’s really committed to it,’” said Rob Moore, Paramount’s vice chairman.

Over the weekend, the movie attracted both females and males in nearly equal measure but appealed to older moviegoers. The crowd, 67% of whom were over age 25, gave the film a B+ CinemaScore.

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Overseas, where Pitt traveled to premieres in London, Paris and Moscow, the film grossed $45.8 million while playing in 25 countries. Though the film did well in the United Kingdom and Australia, it performed best in South Korea, raking in $10.3 million in the country.

As for “Man of Steel,” even though the Superman tale didn’t hold up as well as predicted, it still crossed the $200-million mark domestically. The film has now sold $210 million worth of tickets in the U.S. and Canada.

Also in its second weekend at the multiplex was the R-rated comedy "This Is the End," which now looks as if it will have a long life in theaters. The inexpensive film starring Seth Rogen, James Franco and Jonah Hill only saw its ticket sales drop 37% to $13 million, raising its domestic total to $57.8 million.

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