We used to sing:-

Say what you will,
School dinners make you ill,
And Davy Crockett died of shepherd's pie.
Our school din-dins
Come from pig bins
Out of town.   (Parody of a Max Bygraves song popular at the time)

And we called that stodgy steamed pudding with bits of fruit in 'Boiled Baby'.

Steve, I'd completely forgotten those spring-loaded scoops, wielded by ferocious dinner ladies with red angry faces! And as for spam fritters...