I might add that this Middle School was very near a small shopping precinct called Anglia Square. In Norfolk there's a famous parody of the Three Kings carol:-

"We three kings of Anglia Square
Selling ladies underwear.
They're fantastic - no elastic,
Seventy pence a pair!"

There was also,

"We three kings of Orient are,
One in a taxi, one in a car,
One on a scooter blowing his hooter,
Following yonder star."

and

"While shepherds washed their socks by night
All seated round the tub,
A bar of Sunlight soap came down
And they all began to scrub."

My pupils were forbidden on pain of death to sing these during a carol concert, but I was almost sure I heard the naughty words many a time.