The light is dim. Foliage trails over the walls and roof. All around us are the chittering sounds of monkeys, birds and insects.
Forty pupils are sitting expectantly, waiting to experience a day in the rainforest, one of nine key stage I and 2 education sessions offered at Drusillas Park in East Sussex.
Usually the session begins with a series of slides to evoke a sense of the heart of the forest. Today, though, the projector has broken down, so education officer Nicolette Palmer uses pictures and artefacts to give an idea of the rich plant and animal life to be found in a tropical habitat.
The children, from Ivy Chimneys county primary school in Epping, Essex, are amazed to learn there are spiders the span of a dinner plate, flowers one metre across and tree 83m tall.
There is a discussion about the useful things we get from rain-forests, such as medicines, make-up, rubber, chocolate and paper, and about the threat to the envi- ronment and the tribal people's way of life if the forests are lost.
Then the star of the show appears: Zoe, a South American rainbow boa.
Children gasp as she coils herself loosely around Nicolette's arm and flicks her tongue out to smell the air.
Zoe is not poisonous, the children are assured. Instead, she squeezes her prey to death.
The children are invited to stroke her soft, silky skin. Zoe has been handled since she was a baby, so she is used to it. "If she didn't like it, she'd get shirty and bite you," says Nicolette, "but you can tell that she's happy."
Zoe goes back in her box and out of a tank comes Dustbin Man, a nine-inch long giant African millipede. Dustbin Man, who is vegetarian, has only 500 legs because he is not yet fully-grown.
His full quota will be 700.
Ivy Chimneys primary has opted to have its education session at the beginning of the visit. "I think the children get much more out of the zoo if they do this first because it focuses their minds and sets them thinking," says Julia Dimon, their head teacher. "It brings the concept of habitats and food chains to life, so the animals they see mean more to them."
There are no elephants, lions, tigers, giraffes or bears but the 50 species it has, including meerkats, penguins, flamingos, llamas, emus, wallabies, monkeys and lemurs, have been chosen to illustrat conservation issues.
This lively, friendly animal park has been painstakingly designed to arouse children's interest and curiosity. Labels on each enclosure tell visitors much more about the inhabitants than simply their species and native country. Each creature has been given a name and there are notes of relevant personal information, including what they eat, whether they have had babies and any recent incidents in their lives.
Two male lemurs recently had a fight but, according their label, their wounds were only superficial. A notice on the otters' enclo sure explains that the keepers hide their food in different places to give them something to do. In nature, foraging takes up a large part of each animal's day.
Here, animals roam in paddocks or glass-fronted enclosures which are open to the sky. The meerkats' area incorporates a tunnel leading to a glass dome at ground level, enabling children to observe them at close quarters.
The philosophy is to combine education with fun. This is especially evident in the non-living 'exhibits, such as a display in the entrance area illustrating the origins of life on Earth. "Let's go back to the beginning, 4,500 million years ago, when the Earth began to cool," says a sign. Rumbling sounds emanate from a fiery-looking rock.
A little further on, live crocodiles, the closest things we've got to prehistoric lizards, share their pool with a woolly mammoth (depicted in relief on the wall) and a large, roaring dinosaur head which moves from side to side.
There are things to do everywhere. Story boards, with the answers to questions hidden under flaps, pose challenges ("Are you as heavy as a wart hog? Can you pull as much weight as a horse?") and in a farmyard setting you can milk a pretend cow or climb inside an egg.
* Drusillas Park: Alfiston, near Berwick, East Sussex BN26 5QS. Tel: 01323 870656; fax: 01323 870846; e-mail; firstname.lastname@example.org www.drusillas.co.uk
Open from March 26, 10am-6pm, from November 1, 10am-5pm.
Admission: pound;3.65 children and adults, pound;3.15 each for groups of more than 10. Adults free at a ratio of 1:7 children. Cost includes an education session and activity sheets. Nine KS1 and 2 education sessions offered, each with its own free teacher's pack. The Discovery Centre, a double-decker bus, has two classrooms and a library. Education officers: Gemma Walker and Nicolette Palmer.