Students were “delighted” to be awarded for being eco-friendly for a third consecutive year.

St Gregory’s Catholic Science College, in Donnington Road, Harrow, is one of only three state maintained secondary schools in London to hold the Eco Schools Green Flag Award.

To earn this accolade, a school must already have achieved bronze and silver awards and must show that they have achieved significant and sustained impact in their school across a number of eco criteria.

This may include minimising litter and waste, saving energy and embedding the ethos of “Reduce, Reuse, Recycle” across the school curriculum.

In addition, schools have to show major progress in one project area, which for St Gregory’s is their Eco Garden.

The Award, which was first achieved by St Gregory’s in October 2012, is only valid for two years, after which the school has to reapply to prove that they are maintaining and building upon the Eco Schools’ criteria.

Head teacher Andrew Prindiville said: “Our whole school community is absolutely delighted to have achieved this award for the third time, reflecting the sustained hard work, commitment and support from pupils, staff and governors combined.”