Grammatically incorrect tweets by Rihanna, Justin Bieber and Lady Gaga are being used as teaching materials to help Brazilian students learn correct English.

In a crafty attempt to help its students learn in a modern, engaging way, the Red Balloon English language school, which has branches in several Brazilian cities, has been getting its pupils to critique celebrities' badly written tweets. The "Celeb Grammar Cops" are a team of children aged between eight and 13 who respond with the grammatically correct edits to celebrity solecisms. The team was formed when Red Balloon teachers became worried that their pupils were absorbing too much grammatically incorrect or colloquial English in tweets by entertainers. Once the Cops have located their target, they then use the @RedBalloon twitter account to revise the tweets, sending suggestions for corrected versions.

Although the Cops have dealt with an array of tweeting actors, such as John Cusack and Charlie Sheen, musicians are some of the worst verbal offenders. Eleven-year-old Carolina took umbrage at a tweet from Rihanna: "@She's my rock so I hold on to she tight!!!" Carolina responded "Hi @rihanna! I love your songs. My name is Carolina. I'm 11 years old. It's not to she, it's to her. bye bye". Milena, 10, was hot on the heels of Lady Gaga's spelling of "crowd": "that phoenix crowed was completely and utterly insane. Just did #4showsin4days in three states. I will be sleeping for the next 24hrs". Soulja Boy's tweet, "She not a queen if she don't belong to a king" came under the scrutiny of Mayara and Ana, who responded: "We're 11 and 8 years old. Did you mean "she's not" and "she doesn't"? :)".

So far, none of the celebrity dunces have responded to the Grammar Cops' tweets.