Since the mass school shooting in Parkland, Florida, that left 17 Marjory Stoneman Douglas High School students and faculty members dead, the high school survivors started the #NeverAgain movement to fight for gun reform. The activists also planned a “March For Our Lives” in Washington D.C., and celebrities are taking it upon themselves to support the movement both financially and vocally.

Dozens of celebrities took to Twitter to offer words of encouragement to the Parkland students and praise them for their activism.

“It’s President’s Day and Chief Little Hands has been busy tweeting from his golf resort, a chip shot away from the latest bloody school shooting. He was hoping to play a few holes while grieving families are busy digging them. I support @cameron_kasky #neveragain,” actor Jim Carrey tweeted, tagging student activist Cameron Kasky.

Dear Evan Hansen star Ben Platt tweeted about the Stoneman Douglas High School students as well.

“I don’t care what you think of the amazing kids using their voices,” Platt wrote. “I don’t care if you want to blame mental health, which is a valid issue to be sure. We have the worst gun control. So we have the most shootings. We need stricter regulation. Any resistance is baffling & wrong.”

Barbra Streisand also tweeted out her support along with an article from Esquire about the movement.

“The Kids are right. #NeverAgain,” Streisand wrote.

George and Amal Clooney donated $500,000 toward the March For Our Lives, saying they were inspired by the young activists’ courage and eloquence.

“Our family will be there on March 24 to stand side by side with this incredible generation of young people from all over the country, and in the name of our children Ella and Alexander, we’re donating 500,000 dollars to help pay for this groundbreaking event,” George said in a statement. “Our children’s lives depend on it.”

Shortly after the Clooneys’ donation, Oprah Winfrey tweeted a supportive response announcing she would also donate $500,000 toward the Stoneman Douglas students’ cause.

“George and Amal, I couldn’t agree with you more,” Winfrey said. “I am joining forces with you and will match your $500,000 donation to ‘March For Our Lives.’ 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.”

Singer-songwriter Demi Lovato invited some of the survivors on stage with her on the first night of her “Tell Me You Love Me” tour.

Several talk show hosts like Jimmy Fallon and Jimmy Kimmel spoke about the cause on their shows, and Fallon said he will march with them in Washington D.C. Ellen DeGeneres also hosted three of the teens, and at the end of the segment, she and Shutterfly donated $50,000 toward the march as well.

Other celebrities, including the Kardashian sisters, Justin Bieber and Harry Styles, promoted the March For Our Lives and its petition.

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“On March 24th, students and families across the country will #MarchForOurLives and demand that leaders take action to end gun violence in our schools & communities,” Kim Kardashian-West tweeted, along with a link for people to find marches in their area.

“On March 24, students & families across the country will #MarchForOurLives!!!” Khloé Kardashian tweeted. “We have to support them and demand that our leaders take action to end gun violence in our schools & communities.”

“I just signed the @AMarch4OurLives petition, and you should too. H,” Styles tweeted.