The Holy Spirit College students had already tasted success at school, but this was a new and different crowd.

Fortunately, they were a hit.

As the band played popular songs, shoppers whipped out their iPhones for videos, threw coins to the musicians and toddlers bopped along to the tunes.

These included You Can't Stop the Beat from Hairspray, What Makes You Beautiful by One Direction, Get Lucky by Daft Punk and American Idiot by Green Day.

For 17-year-old Alex from Fairy Meadow, busking was a way to alleviate boredom during the holidays and have some fun.

"This is my first time busking ever," he said.

"I was a little bit nervous that I'd forget what I was playing, but I was all right.

"It's not so much about the money, when people stop and watch that's more rewarding."

The guitar player hoped to enter the music industry, citing Green Day's Billie Joe Armstrong as his inspiration.

Originally, the three friends performed together for a school assignment, said trumpet player Jack.

"We were at school and I had to do a music assessment," he said.

"Theo and I decided to play [You Can't Stop the Beat] and then we roped in Alex to play that with us.

"Teachers asked us to play it at a school event and it was really fun, the crowd really liked it."

The 16-year-old said even though he wasn't sure of his career path after school, music would always be a part of his life.

"You know how people really love praying and going to church?" he said.

"It's the same sort of thing.

"It's really soulful."

His school-mate Theodore, 17, has decided to become a musician, hoping to enter the Australian Institute of Music or JMC Academy as a drummer or sound engineer after the HSC next year.

"Busking was good practice and it was exciting to bring out the drum kit," he said.

"It's good fun, and if we can't get any gigs in cafes this is a great opportunity," he said.

"We'll try and get it going as a band, so hopefully it works.

"People have been interacting, they sort of get the songs we've been aiming for, so that's good."

Nerves weren't an issue for the Port Kembla resident, who was used to performing in front of a school audience of almost 500 people.

"Hopefully we get better and busk in Sydney, maybe Pitt Street," he said.

His mum Gina Papadopoulos said she was excited they were playing in the mall.

"They just love playing and they want others to enjoy it," she said.

"Eventually they'd like to get gigs, so this is a good way."

The proud mum kept her distance while they were playing, but occasionally stepped forward to throw some coins their way and support the group.

"They're very passionate about their music and they're a gorgeous group of boys," she said.