Jonathan Mason, of Belton Lane Primary School in Lincolnshire, claimed in a letter to parents that many students approached him with concerns "about the impact of sending Christmas cards on the environment."
"Throughout the world, we send enough Christmas cards that if we placed them alongside each other, they'd cover the world's circumference 500 times," Mason wrote, according to Sky News. "The manufacture of Christmas cards is contributing to our ever-growing carbon emissions."
Mason suggested to parents who want to send a card to "send one card to the whole class" instead of individual ones, in an effort to "save money and the environment."
Parents criticized the "Grinch-like" decision, including one who told the Daily Mail, "Why should children have the joy of taken out of Christmas? Why can't all these cards be recycled anyway? And I buy a lot of Christmas cards for charity."
"It's great to see them come out of school with their cards and a smile on their faces. It's a Christmas tradition they have had for a long time and now they are taking it away," the unidentified parent said. "I know we have to protect the environment, but these are a few Christmas cards once a year and to be told about this on a piece of paper seems contradictory."
Another mother said: "Telling people to stop sending cards in a letter sent out to hundreds of kids stinks of rank hypocrisy. ... They are mostly recyclable anyway. I agree that environmental issues are important but I don't see recyclable Christmas cards as a massive contributor to these problems."