At Arthur Ashe Stadium Saturday, teen idols -- including Fifth Harmony and Ariana Grande -- paraded around the tennis court and performed on stage to adoring shrieks from young fans.
Some of the world's best tennis players -- Roger Federer, Rafael Nadal and Serena Williams -- got their share of swoons, too, when they took to the court for a good-natured challenge against young players.
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But despite the serious star power showcased at the U.S. Open's Arthur Ashe Kids' Day in Flushing Meadows, first lady Michelle Obama easily won the biggest applause.
As part of her Let's Move campaign to fight childhood obesity, Obama spoke to the thousands of kids at the 18th annual entertainment event meant to honor the late tennis champ and humanitarian Arthur Ashe, who won three Grand Slam singles titles including the 1968 U.S. Open.
For her part, Obama delivered a message on the virtues of fitness, hard work and discipline, using tennis and the accomplishments of players such as Williams and her contemporaries as examples. "If you want to be good at anything, you have to work at it," she said. "You have to show up every day. You have to do your homework every single night with no exceptions, and you have to work hard for everything you do."
She also lauded the U.S. Tennis Association's recent initiative that will install 5,000 new kid-sized tennis courts nationwide and train 15,000 new coaches, trainers and teachers over a three-year period to acquaint younger children with the sport.
Obama ended with a message of love and pride, adding that she and President Barack Obama can't wait to see what the kids gathered in the stadium accomplish. "We love you all so much," Obama said.
The ticketed stadium show was the main draw at Kids' Day, where security was increased because of Obama's appearance. Throughout the day, kids and their families also took part in face painting, storytelling, tennis for children 10 and under and a juggling workshop.
It was 9-year-old Imani Davis of Newark's second time at Arthur Ashe Kids' Day -- she came with her Boys and Girls Club summer camp. Davis said she loves seeing celebrities and the stars of her favorite sport.
Reyana Williams, 22, a camp counselor for the Boys and Girls Club, said the annual trip is good for the kids. "It broadens their horizons so they can see everything around them, and see more things -- more than just Newark, New Jersey," Williams said.