Students used to refill bottles with filtered water and many were using single use plastic bottles.
Te school decide to give one free biodegradable bottle with the school crest. The bottles degrade fully within five years if they end up in the natural environment.
The new bottle will be launched by Coastwatch Europe founder and ecologist Karin Dubsky at a ceremony in the school on Friday.
Inspiration came from biodegradable bottles being used by cyclists in the Tour de France.
Extra biodegradable bottles can be purchased for €5, with €1 from each sale going to fund the fight against breast cancer.