Housebuilder Bellway, currently constructing homes at Francis Gardens, led the competition at Silver End Academy.
They provided two pumpkins for each of the school’s 14 classes, along with two additional ones for the reception classes, who have been reading the book Pumpkin Soup in class.
The pumpkin donation was part of Bellway’s sponsorship of Otto’s Pumpkin Patch in Cressing.
Bellway Essex site manager Billy Granshaw and sales adviser Nicola Doig judged the designs.
They presented the winning class with a voucher for classroom games.
The school council will now compost the pumpkins for use in the school’s new gardening project.
Silver End Academy headteacher Sarah Meares said: “The children have been very excited about this.
“They were asked to use their imaginations and think about autumn and harvest themes, rather than just Halloween, for their designs.”
Bellway’s Billy Granshaw said: “I was really impressed by the pumpkin designs the children came up with.
“They were extremely imaginative and eye-catching and it was very hard to choose a winner.
“We’re pleased to support the school with this competition.”
Bellway is currently building 94 homes at Francis Gardens, Boars Tye Road, Silver End.