Organised in partnership with UNEP, the United Nations Environment Programme, it will be attended by 800 l0-12-year olds, including 600 whom British Airways, the main sponsor, is flying in from around the world, half of them from beyond Europe.
The morning sessions, presented by the children themselves, will be devoted to: waste and recycling, wildlife in danger and sustainable development, climate, rural and city living. To help answer queries, the Information Technology Department at Brighton University is providing access to the Internet. Outings, workshops and drama will be arranged for the afternoons.
Debbie and 14 other eight to 12-year-olds are members of the Junior Board of Drusilla's Zoo Park at Alfriston, East Sussex set up by Michael and Kitty Ann, the owners six years ago. The board meets three times a year. Recently its advice has been sought by Marks Spencer and Stena Sealink.
"The idea for a conference grew out of the members' widening role as 'consultants'", says Michael Ann. "They had no hesitation in deciding that the environment should be the subject and that children from the whole world should be invited! How could we fail to rise to such a challenge? "UNEP was delighted by the idea because one of the resolutions at the Earth Summit in Rio said there should be more consultation with children on environmental matters. "
In recruiting the British delegates, East Sussex County Council asked directors of education throughout the country to identify schools involved in relevant projects. Scouts, guides and other groups are also being contacted.
Children from around the world are being found through UNEP. Already two young Masai from Kenya have signed up. Everyone will stay, together with their escorts - who are being offered half-price flights - in local hotels and guest houses. The children's organising committee of 10, headed by Debbie Simmons, includes Russian, Chinese and Hungarian members living in south-east England, will have the final say in selecting the delegates. Some of them will give presentations.
But will the conference have any hope of producing a more practical impact than all those well-meaning adults at previous conferences?
"Every delegate will be asked to choose one of the projects exhibited at the conference to take back home and start up for themselves," says Debbie. "We want action, not words. Through UNEP we shall also expect governments to report back to our next conference on what they have done about the resolutions we pass. There is no time to be lost."
o Full details of the Leave It To Us conference from Conference Associates and Services International Limited. Tel: 0171 499 0900. Delegates Pounds 94 (escorts Pounds 42), four nights' full board Pounds 99