The Parkland teens have star power behind them.

Oprah Winfrey and Steven Spielberg each threw $500,000 on Tuesday to March For Our Lives, a group organized by survivors of last week’s school shooting in Broward County, Fla., matching an earlier donation from George and Amal Clooney.

“George and Amal, I couldn’t agree with you more. I am joining forces with you and will match your $500,000 donation to ‘March For Our Lives,’” Winfrey tweeted. “These inspiring young people remind me of the Freedom Riders of the 60s who also said we’ve had ENOUGH and our voices will be heard.”

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Spielberg and his wife, Kate Capshaw, praised student activists in Florida and beyond for “demonstrating their leadership with a confidence and maturity that belies their ages.” “Kate and I applaud their efforts to take a stand for the benefit of this and future generations,” they said in a statement obtained by Deadline. “They are an inspiration to us all, and we are joining in this movement with a donation of $500,000.”

Former DreamWorks CEO Jeffrey Katzenberg and his wife, Marilyn, reportedly also matched the Clooneys’ half-million-dollar donation.

George and Amal Clooney had announced earlier Tuesday they would help bankroll the teens’ gun control march next month in the name of their eight-month-old twins, Ella and Alexander, as well as attend the March 24 rally. “Our children’s lives depend on it,” the actor said in a statement to Deadline.

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The teens of Marjory Stoneman Douglas High School, where an AR-15-wielding gunman killed 17 people last Wednesday, have since led the charge for gun safety legislation through media interviews and viral tweets calling out the gun lobby and lawmakers who benefit from it. Kids and their families will march on Washington, D.C., next month in an appeal to Congress, while several major cities have planned sister marches.

Money raised will go toward “the incredibly difficult and expensive process that is organzing (sic) a march like this,” Stoneman Douglas junior Cameron Kasky wrote on a GoFundMe page. Leftovers will go to the shooting victims’ funds.

“Here’s a time to talk about gun control: March 24,” Kasky told CNN on Sunday. “My message for the people in office is, you’re either with us or against us. We are losing our lives while the adults are playing around.”