The future of written English will owe more to Hollywood films than Dickens or Shakespeare, if the findings of a study into children’s writing are anything to go by.

The analysis of 74,000 short stories found that their written work was littered with Americanisms, exclamation marks and references to celebrities.

Researchers who looked at the entries to a national competition found they were increasingly using American words such as garbage, trash can, sidewalk, candy, sneakers, soda, cranky and flashlight.

The stories, written by pupils aged seven to 13, show how fairy cakes are referred to as cupcakes and a dinner jacket has become a tuxedo.

‘Smart’ is now often used for ‘clever’ and ‘cranky’ for ‘irritable’.

Celebrity culture also has a powerful influence on children’s work, with Simon Cowell and Argentinian footballer Lionel Messi among the famous names cropping up repeatedly.

But pupils are let down by basic spelling, punctuation and grammar, according to the study by Oxford University Press, which looked at the entries to BBC Radio 2’s ‘500 Words’ competition.

Children stumbled over simple spellings such as ‘does’ and ‘clothes’ and struggled to use the past tense correctly, often saying ‘rised’ instead of ‘rose’ or ‘thinked’ instead of ‘thought’.

Researchers also found that punctuation was underused, especially semi-colons and speech marks. Some did not know how to use capital letters.

However, exclamation marks were overused. Researchers found 35,171 examples in total, with some young writers using five at a time.

The study of more than 31million words will be compared with future research to see how written language evolves.

Popular US fiction such as the Twilight vampire novels and films is thought to be fuelling the increasing use of American vocabulary and spelling.

Modern technology was also influential. Out of almost 300 references to ‘blackberry’, nearly half referred to mobile phones.