I am in a classroom. Receiving education. But education as I know it - as anyone knows it - it certainly ain’t.

For one thing, the teacher has just walked in with a big box of drugs. She proceeds to open it up and pass the contents around the class. It’s a box full of oblivion - everything the confirmed junkie could ever want: crack, cocaine, heroin, opium, amphetamines, LSD, ecstasy, magic mushrooms and three different types of marijuana.

Looking around, I notice that everyone else in the class is dressed up like a police officer. Even the teacher is in uniform. Soon, no doubt, a white rabbit will appear, closely followed by the Mad Hatter and the Queen of Hearts.

No, this is not from a script by a Lewis Carroll write-a-like, but a real class at Havering college of further and higher education, where the idea of police training in the community is being turned into reality. The student officers - 10 men and four women - are being taught to recognise illegal substances and how they fit with the 1971 Misuse of Drugs Act. And the samples - on loan for the day from Hendon police training college - are most definitely not for sampling, all sealed up as they are in secure transparent packaging.

Our job is to identify which drug is which - a more difficult task than you might think, when so many of them look the same. I am working with trainee officer Jacklyn Bennett, and between us we manage to score a miserable four out of 14 - which at least shows we have both led blameless lives. I am learning something, though - such as how to spell benzodiazepine, and that toot, nose candy, fluff and kicking powder are all street names for cocaine.

“All right,” says our teacher, PC Julie Chandler, when the samples are safely back in the box, “we’ve found some white powder on our suspect. Do we try and find out what it is by tasting it?” “No,” choruses the class.

“No,” repeats Julie. “We don’t taste it. We don’t sniff it. We send it off to be analysed.” Hang on, I want to say, didn’t Inspector Regan and Sergeant Carter always sniff and taste before telling chummy: “You’re nicked”?

When the classroom session is over - the participants have had handouts in advance and seem to know their stuff pretty well - we get out into the spring sunshine for the practicals. Both staff and students put a lot of emphasis on how practical their course is. At 31 weeks, it’s considerably longer than the 18-week “parent” course at Hendon, because the work they do in the college is integrated with spells out at police stations in the outer London boroughs of Havering and Barking and Dagenham.

“The idea is that we give them the theory,” says Dave Norton, one of the two sergeants in charge of the training. “They practise it in role plays, and then they put it into practice out on the streets. It’s different from Hendon in that there they don’t get ‘live’ experience until the end of their course.”

The other aspect of the Havering course that Dave emphasises is community involvement. “Being in the college is very much a two-way street. It’s helping to demystify the whole area of police training. The recruits are wearing uniform in public and getting used to being in the public eye right from day one. And the other students are interacting with police officers in a normal way. They see we’re just like the plumbers and the electricians.”

At first, however, not every student relished having the police in their midst. Cries of “pigs” and the odd “oink, oink” were not unknown when the course started up back in November. But that died away as the other students grew used to having them around.

“Now we’re thought of as just another course,” says Dave, who points to the other contributions he and his fellow trainers make to college life, such as teaching self-defence and running drug awareness sessions.

Outside in the college grounds, we are about to see some of that integration put into practice. Adam, who when he’s not helping the police with their enquiries, works in the college library, is getting fixed up with several wraps of puff. Ryan, formerly a Havering student and now interested in joining the police himself, is into the kicking powder, and he’s practising a “rapid sniffing” routine, just to give the scenario an extra whiff of authenticity. The pair have been grassed up by Brian, one of the college’s caretakers, who describes himself as the “Charlton Heston” of role players.

On to the scene come our two pairs of officers. Their brief is to get the “story” from Brian, then to apprehend and search the two suspects. The rest of us - half a dozen other trainees, plus Dave and Julie, clipboards at the ready - follow them about.

The first pair approach the suspects who are somewhat self-consciously larking about behind a wooden outbuilding. PC 216, otherwise known as Rob, soon shakes down Adam and finds his stash hidden in his sock. Sadly, his partner John doesn’t have so much luck and misses the coke Ryan has slipped into his little money pocket.

Dave and Julie give instant feedback, praising much of their work and making light of the drugs they missed. “It happens,” says a philosophical Dave.

Now it’s the turn of Marie and Andy. Marie slips round the back of the shed to cut off any escape, while Andy confronts the two men head on. They too fail to find Ryan’s money-pocket stash, but that doesn’t matter too much, says Julie, because now they, and all of the others looking on, will always remember where to look in the future.

Back in the canteen, Dave reflects on the exercise. “It’s not going to be exactly like it is in real life,” he says. “But what I’m after is a stepping stone between the classroom and what it’s really like out there on the streets.”