Consciously Coupled Onstage! Gwyneth Paltrow & Ex Chris Martin Duet For Son's School

Gwyneth Paltrow and Chris Martin brought down the house when they rocked a duet together at fundraiser and RadarOnline.com had the exclusive details from the happily divorced duo's big performance.

The Oscar winner, 45, and the Coldplay frontman, 40, performed at their son Moses' school fundraiser parent talent show on Saturday, February 24 at the swanky Roosevelt Hotel in Hollywood.

"Gwyneth opened the show on stage singing "Despacito" by Justin Bieber by herself, and the crowd went wild," a witness dished to RadarOnline.com.

Wearing a black pants suit with a long sleeved black sweater and her hair in pig tails, Paltrow also sported her giant diamond ring on her left hand. (The pair is engaged to longtime boyfriend Brad Falchuk, 46.)

After her debut, Martin joined her on stage.

"Chris came up and they sang 'Bombeleo,'" the source told RadarOnline.com about the Gipsy Kings tune. "Then they sang another Cuban song together."

"Gwyneth and Chris were so friendly with each other and the other parents, it was a great night," the insider added.

The Country Strong actress sang all of the songs in that movie when she played a struggling country singer.

Paltrow and Martin famously "consciously uncoupled" in 2014. While she is engaged to Falchuk, Martin is currently dating much younger actress Dakota Johnson, 28.

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