'I Recognized Her Creativity' (Exclusive): Billie Eilish's Choir Teacher Recalls First Impression of the Star

"She always sang beautifully in tune, which is a gift to a choir director," Los Angeles Children's Chorus retiree Mandy Brigham tells PEOPLE of Eilish

It's a proud moment for Mandy Brigham to see her former student, Billie Eilish, thrive as a musician.

After Eilish gave Brigham a heartfelt shoutout during her 2024 Oscars acceptance speech, the former Los Angeles Children's Chorus teacher is reflecting on the "What Was I Made For?" superstar's time as her student.

"I have a very clear memory of Billie on her first day in choir. I remember right where she was sitting, and I remember she was sitting up really straight," Brigham tells PEOPLE. "Everyone's pretty quiet at the first rehearsal because no one comes in knowing anyone else, but she was just really tuned into what was going on."

Before retiring after the 2022-2023 season, Brigham spent 22 years as a director at the Los Angeles Children's Chorus and oversaw both young and intermediate groups of singers. She got to know the O'Connell family through first teaching Billie's older brother Finneas, whom she helped prepare for an opera at Santa Monica College during his time as her student.

Having already known Finneas and their parents Maggie and Patrick, Brigham knew Billie came from a musical family and quickly took notice of the future Grammy winner. "As I got to know her, I just realized how much she loves singing," says the retiree. "She always sang beautifully in tune, which is a gift to a choir director because you can place that person somewhere and know that others will follow their lead."

Over Brigham's four years teaching Billie, she began to realize the young performer was also interested in songwriting. "From an early age, I recognized her creativity. She's really her own person," she recalls. "When she was a little bit older, she'd have a notebook, and she'd jot down ideas for lyrics and stuff."

Later in Billie's time with the LACC, Brigham's choir embarked on international tours to Japan and British Columbia. By the latter trip, the musician had released early singles like "Six Feet Under" and "Ocean Eyes," which were gaining traction online. "We were all aware of that, and everybody was excited," says the teacher.

Since becoming a household name, Billie's remained connected to her roots. She featured the LACC in her Disney+ conce -

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rt special Happier Than Ever: A Love Letter To Los Angeles and surprised the young performers with a visit while they worked on the project at Capitol Records' studio in L.A. "She was so incredibly kind to them, giving out hugs and all that sort of thing," says Brigham. "I think that was very, very special and memorable for them."

The "Bad Guy" singer has also continued to recognize Brigham's role in her life, even before mentioning her at the Oscars. "When I retired last year, there was a tribute video made," she says. "Billie, Finneas and Maggie all recorded a little, I guess, 'thank you' to me, and it meant a lot to me."

The "Happier Than Ever" hitmaker has also made quite an impact on the LACC members that've come after her. "They get really excited about Billie being in the choir," notes Brigham. "When we talk to students at auditions every year, we'll say, 'Well, how did you find out about the chorus?' They said, 'Well, Billie Eilish was in it.'"

Billie then mentioned the teacher while accepting Best Original Song for her Barbie soundtrack hit "What Was I Made For?" at the Oscars earlier this month. Brigham — who usually tunes into the awards show — was at the Indian Wells Masters Tennis Tournament. "Then, all of a sudden my phone exploded," she says. "I think disbelief would be the best way to describe how I was feeling."

While the LACC has many alumni who've gone on to become successful in opera and classical music, Billie is certainly the biggest star to come from the organization — which Brigham says is a testament to its teachers' approaches.

"Our goal is to train the singers so that they can sing beautifully and with a really healthy technique no matter what kind of music they decide to sing," she says, adding that "it's worked really well" for Billie.

Getting mentioned on stage at the Oscars isn't the kind of recognition a teacher like Brigham necessarily expects, but she says the moment felt "amazing."

"As a teacher, when you hear that a student knows you believed in them, that's really a gift," she says. "Your hope as a teacher is to just let students know that you believe in them and to help empower them to pursue their dreams and develop their gifts. And so to have that affirmation was very special."

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