Staff and children turned Thomas Willingale School in The Broadway, Loughton, into a "sea of pink" when they held their own Race for Life fundraising event.
The day has so far raised £3,651.28 with more donations still being received.
Headteacher Teresa Phillips said: “As many of us in our school community have been affected in some way or another by cancer we decided to run as a school to raise funds for Cancer Research UK, to aid their vital research and treatment, and have fun at the same time.
“We also hoped that by preparing for the event by running laps of the sports field at each PE session, it offered the chance for the children to build on being active and healthy.
“On the day the children from Nursery to Year 6 and staff had a fantastic time and the school was a sea of pink. The sum raised so far is a staggering £3,651.28 - way above our target - and money is still coming in.”