Inschool Media, a company of pupils and adult business advisers at Denefield school in Reading, was awarded the contract to promote the 13th instalment of A Series of Unfortunate Events.
The book by US author Lemony Snicket, aka Daniel Handler, will be published on October 13. The series, which chronicles the lives of the three Baudelaire orphans and the machinations of their evil Uncle Olaf, is second only to Harry Potter in terms of popularity with British children. UK sales of the series have topped pound;5 million.
Inschool Media won the marketing contract based on ideas for project packs for pupils and teachers, including bookmarks and vouchers, lesson plans and instructions for a writing competition.
Pupil company directors carried out research to find out what was popular with pupils and made suggestions for the packs, which were then made up over the summer holidays. So far, more than 1,500 schools have signed up for the packs.
Nicole Waefler, 17, has worked for the company since December. She said:
"My friends can't believe I'm working on something like this. It's really exciting and much more practical than just doing business studies."
Nicole is taking A-levels in history, politics and textiles.
Layla Rea, 26, the company's managing director, said: "This means everything to us. We started off in a tiny cupboard with two laptops but have come such a long way. It proves to the pupils they can get involved in business and be very successful."
Inschool Media is the youngest full-service media company in the UK with a head office at school and meetings squeezed in at break times. Earlier this year, the company ran the Adidas +10 World Cup campaign for secondary schools.
It is one of five companies run by the school under the holding company Denefield Enterprises Ltd. The others include a school shop, a web technology company and a school trip service.
The school was selected in a pilot to benefit from an entrepreneur-in-residence under the Government's Enterprise Insight scheme to promote links between business and schools in 2003.
Eric Joint, headteacher, said: "This is fantastic news for the school. The whole ethos on which we set up the company was so that students could gain a real insight into running real companies.
"The fact we are bringing in such first rate contracts proves we are a force to be reckoned with."
WHAT YOU CAN GET FOR PUPILS
* A project pack for Year 7 pupils that supports the creative writing curriculum. It is written in the style of Lemony Snicket and includes a separate "dark day pack" with a money-off voucher redeemable at Waterstones, a bookmark and letter from Lemony himself.
* Inschool Media and Egmont Press have developed an 'Unfortunate Teaching Pack'with a series of five lesson plans leading to a competition to encourage children to write their own unfortunate event.
For more information visit www.inschoolmedia.com