Guests included Jaime King and Michelle Trachtenberg.
The annual fundraiser raises over $1.5 million to help keep students in school and on track to graduate.
Before the couple had got back together, they were both thought to have moved on with Emma - niece of Hollywood star Julia Roberts - rumoured to be dating a young British man named Kasper Hogan, while Chord was pictured with TV actress Carlson Young.
She's too young to be able to give someone that kind of commitment." The two stars were first spotted making out in April 2011 at the A|X Armani Exchange and 944 Magazine carnival in Indio, Calif.
VIDEO: Emma sizzles on the Scream 4 red carpet "They're both young kids, they had crushes on each other but the relationship ran its course," a sixth insider tells Us of their breakup.
The actor repeatedly placed his arm around Roberts' waist as they chatted, according to the reports.
Roberts isn't the first big name Overstreet has been linked to - he enjoyed a sporty date with country sweetheart Taylor Swift in February when they attended an ice hockey game together in Los Angeles.
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But most A-listers weren't always living the lifestyle of the rich and famous!
, as well as Liam Hemsworth, Jordan Fisher, Holland Roden, Claire Holt, Emma Roberts, Evan Peters, Maddie Ziegler, Chord Overstreet, Halston Sage, Brittany Snow, Aubrey Anderson-Emmons, Carter Jenkins, and Marcus Scribner.