The teacher added: “They didn’t want to idolise him and for students to think you can prat about and be a bit of a bully and still be successful.”
Lennon attended the school from 1952 to 1957 and formed the Quarrymen, a forerunner of the Beatles, while a pupil there.
His record and antics in school have been well-documented, including detention sheets that revealed his “extremely cheeky” side when they came up for auction in 2013.
Reasons for punishment given by his teachers on the recovered sheets, from when he was 15, include “sabotage”, “fighting in class”, “nuisance”, “shoving” and “just no interest whatsoever”.
He managed to receive three detentions in one day on two occasions in 1955 and 1956.
Lennon’s old desk was discovered in the school attic, where teachers were said to have stored it so they would not have to remember his time there.
The desk, which is an old-fashioned lift-up, will now feature in a display at the Liverpool Beatles Museum with other items from the band members’ schooldays, including Lennon’s enrolment ledger signed by his aunt.
Despite years of refusing to acknowledge its link to pop history, the school is now starting to offer tours of its site for Beatles fans.