A company which makes revision guides has been criticised by the advertising watchdog for handing school children promotional material which could encourage bullying.
Letts Educational produced two types of promotional postcard for an annual online GCSE curriculum quiz, in which teams of school friends compete against each other.
One of the postcards given to schoolchildren, said "I am a wimp" while the other said "I'm a big wuss".
They told pupils: "Attach sticky tape here" and "stick on the back of a mate who doesn't have the bottle for the Letts Challenge".
Bad experience
The Advertising Standards Authority (ASA) received a complaint that the postcards were irresponsible because they could encourage bullying.
It was told one child had had a "bad experience" with them.
Letts said it was very concerned by the complaint, but maintained the cards promoted friendly competition, not violence or anti-social behaviour.
It said it had canvassed teachers' opinions and found they accepted the "humour and innocence" of the cards, distributed in January.
But the ASA ruled the company had been wrong to produce the postcards, because they "might encourage bullying".
It said Letts did not plan to distribute the postcards again and told them not to use the same method in future.