The young singers have been honing their voices for months, singing in large and small groups every week since January.

On Saturday, they finally got the chance to showcase their work, as nearly 900 sixth-grade singers — hand-picked by their elementary school’s music teachers for their vocal talent — sang together at Hayfield Secondary School for the 46th annual All-County Choral Festival.

“It is truly an honor for the students performing today to be a member of this select group of vocalists,” said Kelly M.Harbison, president of the Fairfax General Music Educators Association and a music educator at Canterbury Woods Elementary School.

Led by guest conductor Dr. Jamie Hillman, the students sang a variety of music — from George Handel’s classic “Sing for Joy!” to Joan Varner’s “When I Am Silent,” a tribute to young Holocaust victims.

The song, and the voices of 900 sopranos, moved many in the audience to tears.

“These young singers were truly amazing,” said Hillman, who previously taught music at Phillips Academy and Boston University.

“They’ve only had one day to practice as a complete group, and they came together flawlessly. Their energy and enthusiasm was inspiring.”

In addition to the 900 singers, Hayfield’s auditorium was packed with twice as many family members, including School Board members, school principals and Superintendent of Schools Dr. Scott Brabrand.

“I told parents ‘prepare to be wowed by these singers.’ I think we were all blown away by the talent and organization it took to accomplish this, “ Brabrand said.

Organization was key as music teachers used songs and audience sing-offs to quickly reunite singers with their families and move 2,000 people out of the auditorium in under 15 minutes.

“The festival was a rousing success at every level. We’re all proud of these students and our music teachers for this festival,” BraBrand said.