At the moment when the beat dropped and a man's deep voice blared from the speakers, "Music makes you lose control!" the little girls in their sweats and sneakers turned into position.
On an eight count they had learned an hour or so before, the 50 students inside the gymnasium at Randallstown High School yesterday morning followed the instructions of their teacher, acclaimed hip-hop choreographer and actor Darrin Henson.
Arms slide. Head bob. Chests pop, to the left, to the right. Hands clap. Spin.
"Nice, but only 95 percent," Henson called out to his students, mostly young girls from a nearby dance studio. "Do it again. Let's try it one more time and get everyone on the same page.
No complaints from the crowd. These students from the Studio "A" Modeling, Etiquette and Dance Academy in Randallstown - who had been dancing since 9 in the morning to Missy Elliot's "Lose Control" - were thrilled to have the chance to learn from Henson.
The Bronx native began dancing when he was 5 and has choreographed music videos and performances for artists such as Michael Jackson and Jennifer Lopez.
The studio, founded eight years ago by reigning Mrs. Maryland Adrienne Watson Carver, the studio strives to enhance the personal development of children. Carver saw a collaboration with Henson as a chance to further develop the students' confidence and skill level in dancing.
It was the second time Henson taught the students, having visited in January. In addition to promoting his latest dance video, Darrin's Dance Grooves 2, Henson teaches classes around the world.
Henson, 34, is well-known among the young set. He has taught choreography to artists such as Britney Spears, N'Sync and Usher, and has acted in the dance movie Stomp the Yard and the Showtime hit Soul Food.
"These kids talk about the power of excellence," Henson said. "It's so empowering and powerful. That's why I'm here."
If ballet is about elegance and merengue is about making patterns, hip-hop is all style. There's popping and locking, the intricacies of break-dancing, the clowning of krump, the Harlem shake, the exaggerated zaniness of hyphy and the highly sexualized "grinding," which isn't so popular with parents.
Yesterday's dancing was all G-rated.
"It frees me," said Mya Johnson, 16, of Pikesville, a student at George Washington Carver Center for the Arts who hopes to become a professional dancer. "It puts me in my own world. I'm usually a shy person, but [dancing] makes me feel free."
As the beat pounded, the girls moved in synchronization.
From the rows of students, Henson chose Ca' Lynn Scruggs, 11, of Baltimore and Sydney Sims, 14, of Pikesville to stand on a small elevated stage to show the rest of the class their moves.
"She's dancing with conviction, y'all," Henson said of Scruggs. "Obviously she was hitting the steps, but her face, her eyes pulled me in."
Scruggs, a sixth-grader at Mount Pleasant Christian School, said she's been studying dance since she was 4.
"I kept going because my mother told me to keep on going and never give up," Scruggs said after class.
In the bleachers, the parents of the young dancers watched with glee, snapping pictures and calling out words of encouragement.
"I brought my grandson because he loves to dance. He was very excited," said Sharon Ford, 56, of Baltimore. "I told my daughter, 'The next time I'm gonna be in the class.' I can't do any of the moves, but I was on the sidelines having big fun."
Her grandson, Jabari Adeleye, was too young at 5 to take part in the class, but he stood on the sidelines and shifted his feet from front to back at a rapid pace.
After the class, the girls in the class, and the one boy - Ernest Abdul-Raheem, 14 - swarmed Henson to take photographs and ask for autographs.
"It was very good," said Ernest, an eighth-grader at Windsor Mill Middle School. "Who would ever go through it slowly and help me pick up each move?"