He is so right!
The delivery and acquisition of a song is like a mathematical equation. Children are learning at Little Voices to beat time, read music, listen to others, acquire lyrics and tunes, jump between intervals of notes, breathe, sing together, sing alone, perform with emotion. There is so much to do!
It is like a mathematical equation. We do not always get the right answer but we get marks for our method! When we do get it perfect it is amazing for the performer, the listener, the teacher, the examiner and everyone involved!