Cheeky schoolchildren spelled out a rude word on the roof of their school that is so large it can be spotted from space.

Three students used bricks to create the four letter word on the roof of Sutton Grammar School for Boys and the stunt has remained a closely guarded secret until now.

The word – also a term for a male chicken – is so big it was picked up from miles away by a Google Earth satellite.

One student who wished to remain anonymous admitted: “We moved the bricks into position to mark us leaving the school.

“We decided to do something a little bit out of the norm.

“We didn’t think it would last five minutes as we assumed the roof was visited often by the caretaker – obviously not.

“The semi-secret tradition of school boys was to go to the loft just before their final exams and write their name in chalk on the rafters, some names went back as early as the 1940s.”

Sutton Grammar School, which has specialist status for science, is a selective school for 828 boys aged 11 to 18, and rated outstanding by Ofsted in 2008.

The school’s website, which includes policies on discipline and behaviour and a list of school rules, declares: “Sutton Grammar School is a friendly and disciplined school, with high academic standards and good pastoral care. “It turns out lively, interesting and mature young men, well prepared for the challenges of their adult lives.”

Headmaster of 18 years, Gordon Ironside, said: “I found out when someone pointed it out to me and we remove the message, although the bricks are still up there.

“It was a light-hearted act, but it is a rather public display. I would prefer it if it wasn’t there or if it wasn’t a rude word, but maybe something more political.

“Just a few days ago some other students did the same thing, but with a coded message that didn’t seem to spell anything out. We’ll be removing them permanently this time.

“Also, for health and safety reasons, we don’t really want students going up there.”

Mr Ironside said his upper sixth form students didn’t usually indulge in high-jinks when they left school, as the lower sixth students took exams on their last day, but some did still like to have some fun.

He said: “This year some of the upper sixth boys released 100 very small bouncy balls into the playground and a big cheer went up, it was nice, a light-hearted bit of fun.”

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