Pigs can be a dangerous animal to bring near the classroom. In China, parents have complained over their children's school forcing pupils to raise pigs and grow vegetables.
Chunchang Nanlu Middle School, on the tropical island province of Hainan, used a poverty alleviation fund grant of around pound;700 to buy 36 piglets and had pupils feed them three times a day.
Parents were angry because the pig-rearing sessions were taking the children away from other studies, they said, and did not believe teachers' claims that it was educational.
But the parents did acknowledge the school was being financially astute. Pork prices have been soaring in China because of increasing feed costs and an outbreak of blue ear disease. One parent told the Beijing News: "Each pig can be sold for 1,600 yuan (pound;112), with each class splitting the profit of 1,000 yuan, so of course it is advantageous for the school to continue raising pigs,"
In Britain, just bringing pigs near a school could be enough to cause complaints. Last week it emerged that judges of educational technology awards had criticised an electronic book, suggesting it was potentially offensive to Muslims. The reason? It was based on The Three Little Pigs.