Hugh Breslin of Glen Road, Glenties is running the Barcelona Marathon on March 16 in aid of Edenfinagh National School.
During the coming weeks, sponsorship sheets will be available in various shops in Glenties and parents of pupils will also have sheets.
A spokesperson for the school said: “We are hoping that people will generously sponsor Hugh as he takes on this challenge.
“We also hope to have a number of small prizes on offer for sponsors, as they will be asked to put their thinking caps on and guess how long it will take Hugh to complete this marathon of just over 42km.
“A huge ‘Thank You’ to Hugh for coming up with the idea.
“We wish him every success on March 16.”