The tenors - Zac Ellevson, Wylie Lucas, Lachlan Moss and Kye Meizer - sung the Italian version of Unchained Melody in front of the slab caster.

It comes ahead of the foursome's featured performance at this month's Southern Stars school spectacular.

"To think, I started [singing] when I was younger just singing to my parents and I started performing to eisteddfods. To now, I'm here performing at a steelworks doing something that I'd never thought i'd do in 100 years; I loved it," Wylie said.

"I found it intriguing as hell ... just learning about the way it was all made, and seeing the process and seeing the individual parts all working together.

"For me - someone who loves that stuff who nerds over it - I thought it was great."

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More than 3000 public school students from 100 schools will perform during the Southern Stars 2019 COME ALIVE extravaganza on August 23 and 24.

Two circus troupes, the NSW Public Schools Millennial Marching Band, a rock band, 600-strong choir, 10- strong Aboriginal dance ensemble, a large student orchestra, boy's vocal ensemble and over 2000 enthusiastic dancers will feature this year.

While around 12,000 patrons are expected to attend one of four COME ALIVE shows taking place at the WIN Entertainment Centre.

BlueScope is one of the major supporters of the concert.

Tickets are on sale for Southern Stars 2019 COME ALIVE from Ticketmaster.

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