The relentless pace of the school day, as well as its length surprised me most

Damian Green Shadow education secretary

The lesson is all part of Mr Green's few days inside Southfields Community College, one of three Wandsworth secondary schools that do not select pupils by academic ability.

For the Tory education spokesman, learning the lessons of two consecutive Conservative election defeats means teaching a class too.

At least the subject is one likely to catch the attention of young minds - drugs.

Mr Green is not the first politician to visit the college - "thank you for having me" letters from Tony Blair and David Blunkett are proudly displayed in the school's reception.

'No stunt'

He denies his classroom experience in the glare of publicity is a gimmick and explains that going back to school is designed to correct the "slightly false impressions" politicians often get from merely sweeping in and out on short visits.

"I want to see how we can do excellent work in the system, which is what's happening here," Mr Green said.

Seeing a school work from 7am to 7pm really does show politicians the daily practicalities facing teachers, he argues.

Green's week in school is part of the Tory focus on public services

Asked what surprised him most, Mr Green replied: "The relentless pace of the school day, as well as its length."

The two hours it took him to prepare for his one three-quarter hour lesson have also helped him appreciate the workload for teachers with packed timetables.

That preparation over, Mr Green is ready to face the 13 and 14 year olds of Year 9 who troop quietly into the classroom to learn about drugs law - part of their personal and social education course.

Having completed the register, Mr Green acknowledges a thought in the minds of the observing journalists.

"People say we politicians are out of touch and children like you know more than people like me about drugs," he says.

Drugs facts

As he runs through the answers to a drugs quiz, the suspiciously well-behaved pupils are told prescription heroin is taken mostly by people with cancer "who know they are going to die"; that LSD is dangerous and "it messes with your mind"; and that while drying "magic mushrooms" is illegal, picking them and eating them on the spot is not.

Later, as the lesson turns to the law on cannabis, 14-year-old Miles Debrah tells how he has seen people smoking marijuana in Brixton, as well as campaigning for it to be decriminalised.

Blair and Blunkett are previous visitors to Southfields Community College

And the views of some of the children as they decide how they would sentence some drugs offenders would give succour to the most hardline Tory law and order advocate.

Many of the class would jail a major drugs importer for life and it seems one girl is ready to deliver a five-year prison term to someone caught with a few grammes of cannabis.

Mr Green survives his experience without getting tripped up by any tricky question, and by avoiding writing on any blackboards can not repeat the embarrassment of US Vice-President Dan Quayle when he infamously mis-spelt "potato".

Hardly surprising for a politician, the lesson is more like a lecture than a truly interactive class but otherwise Mr Green's performance does get a thumbs up from the watching professionals.

High marks

Jon Millington, the senior teacher at the school who normally takes the class, said: "If he was a trainee in his first lesson, I would be pleased."

There was a positive verdict too from the most important people, some of the pupils themselves.

Miles Debrah said Mr Green was "quite good", adding: "He's from a political party and I did not expect him to be able to communicate to kids."

His classmate, 13-year-old Samiro Warsame, added: "He was OK but he could have asked us about what we felt about drugs."

A further bonus came from Steven Thomas, who as well as pronouncing Mr Green good for a first-timer, said he would vote for the Tory spokesman: "He looks like an honest guy."

Steven may be old enough to cast that vote when the UK next goes to the polls and as Jon Millington told his class: "If the Labour Party loses the next election, Damian Green will be taking decisions about your education."

In the light of the last two elections, trying to put the Tories in such a winning position might prove an even more daunting task for Mr Green and his colleagues than teaching teenagers.