On the subject of Michael Mangan, he wrote the school song for St Teresa’s School, Ravenshoe, a small town in North Queensland.
It would be a lovely song for any school to sing and aspire to, but the chorus’s last line is, “At St Teresa’s: knowledge, love and truth”, so your school has to fit the syllables. It would also make sense to adjust the lyrics if you don’t have waterfalls, lakes, elevation, flowers and beauty surrounding you.
… and for that matter you would need to ask Michael Mangan and St Teresa for permission.
I can’t see it for sale at Litmus but the school provides the sheet music. You can also listen to Michael Mangan sing it there.
This is my BIAB backing.