A game which involves flipping a bottle of water has been banned from a high school in Norfolk over safety fears.
The bottle flip game sees challengers throw a half-full plastic bottle in the air with the aim of making it land upright.
People now try to outdo each other by performing the trick in increasingly difficult places.
However it hasn't gone down well with everyone and North Walsham High School in Norfolk banned it for "safety reasons" this week.
In a statement on their website they said: "Following a misunderstanding today, we would like to confirm that the 'bottle flip challenge' is not permitted in school.
"Students caught doing this will have an immediate C3 detention. Many thanks."
The school said it "did not want to spoil fun" but minor injuries involving plastic bottles made the ban necessary.
Head teacher Neil Powell said: "Following one or two minor injuries sustained by students when water bottles hit them, we decided that for safety reasons we would ban the practice in school, before a more serious injury occurred.
"We are aware of several schools in Norfolk taking similar action to ban the challenge."
Emma Kenny, child psychologist, said: "I think that the chance of serious injury is very minimal. This is an activity that a lot of children enjoy, every child can afford and will get them moving about and playing together.
"Schools should be honest and admit that having lots of bottles thrown around the playground is annoying but it's not dangerous.
"We seem quite happy for children to sit in front of a TV screen and kill each other in computer games but we ban a game that really benefits them."