By Penny Haslam
BBC Radio Five Live Report
Big British brand names are keener than ever to tap into the children's market - and are coming up with more creative ways of getting their products into schools.
Mentos offers schools free mints and a teaching pack
At Wisbech in Cambridgeshire, pupils in a chemistry lesson are carrying out an experiment involving dropping Mentos mints into a large plastic bottle of cola.
The result is a huge explosion with fizzy drink rocketing into the sky.
It is good fun and the secondary school pupils are impressed.
One boy said: "I can't believe it went that high."
Another pupil said: "The bubbles which got inside the texture of the Mentos made carbon dioxide and that's what made it go up."
The experiment started as an internet craze last summer. It is thought that sales of the sweets went up by 15% as a result.
The Mentos project called Put the Fizz into Science now offers schools free mints, a teaching pack and a chance to win £2,000 of science equipment.
Mentos said the project had been extremely well received by teachers across the UK and that it had been oversubscribed.
"The Mentos project aims to support the science school curriculum and encourage children to enjoy science," a spokesman said.
Earlier this year the government banned the advertising of food and drink that is high in fat, salt and sugar during children's television programmes.
As a result companies are looking for alternative ways to interest younger customers. But there are concerns about classroom advertising.
The National Union of Teachers launched a consultation on commercialism earlier this year called Growing up in a Material World.
It reckons advertisers spend around £300 million a year targeting the classroom.
Marketing expert and businessman William Anderson, who set up the Schools Consortium which brokers deals between brands and schools, has no doubt of the value to advertisers.
"Business gets to build a relationship with consumers of tomorrow," he said.
"If I can make sure the first brand experience of a seven-year-old is extremely positive, they are going to understand that it's positive probably for the rest of their life.
"Brand relationships are established very young."
Some experts have expressed concerns about the way one industry in particular is funding a mass programme of teaching aids in schools about the benefits of nuclear power.
A series of films funded by the nuclear industry and a regional development agency have been widely shown in schools and viewed by thousands of children on GCSE science courses.
In the film on nuclear waste, all bar one of the speakers worked for the nuclear industry.
One worker says: "I do get paid well. The industry expects high professional standards of its employees so naturally that comes with the appropriate awards."
Another is asked whether he is happy working with very dangerous highly radioactive waste.
"I'm really happy. Basically we are working with high level waste back there but it's immobilised in a glass matrix so it's basically safe," he says.
Much of the film seemed to be geared to encouraging recruitment into the industry.
Independent nuclear consultant John Large works for both the nuclear industry and environmentalists. He thinks it is less about science, and would be more suitable for a careers lesson trying to connect with younger viewers.
"It's a blatant piece of propaganda, that's not an educational tool. That's just propaganda, that's glitz.
"One suspects a bit of an agenda here to try and connect things that children are used to in technology like Playstations and this sort of technology."
The film on nuclear waste has proved contentious as pro-nuclear propaganda.
Film maker Energy Foresight's programme manager Derek Wordley said: "There are people out there who at the very word nuclear will pull back and withdraw.
"If they [children] are biased against it by perhaps uninformed or perhaps political viewpoints, then that is surely not a good thing.
"We are aiming here to provide unbiased material which can be used to educate the children."
The film was also aired twice on BBC2's Learning Zone where programmes are recorded for use in schools thereby ensuring their wider use.
A spokesman for BBC Learning said it had been a mistake to broadcast the nuclear waste programme and it had not been cleared before transmission.
Once it had been vetted, BBC Learning placed an immediate bar on repeat transmissions, as it judged some elements unsatisfactory. But due to an administrative error it was aired again 18 months later.
BBC Learning said firmer controls were being put in place and offered an assurance it would not happen again.
It also said it was not practice in the past to closely vet funding packages behind acquired programmes but it now plans to look more closely at this.
Energy Foresight is currently asking for more financial support from industry to roll out another series of similar videos to half of all secondary schools by 2010.
The Department for Children, Schools and Families said there were no guidelines or standards for teachers and schools to follow when using this material, other than their own judgement.
Five Live Report: Classroom Commercials will be broadcast on the Rachel Burden Show at 1130 GMT on Sunday, 9 December. Or download the podcast from the Five Live Report website.