The writing competition comes with a range of curriculum-linked classroom resources and offers categories for children aged 5 to 7 and 8 to 11.
All pupils need to do is write a story that they would love to read in 500 words or fewer.
The deadline for entries is November 8 and the finals will take place in February at Buckingham Palace, supported by the Queen, when 50 finalists will be invited and the six winners revealed. The winners’ stories will be read out at the event by celebrities.
The entries this year will be judged by a six-strong panel featuring singer-songwriter Olivia Dean, children's laureate Frank Cottrell-Boyce, actor Sir Lenny Henry, and authors Malorie Blackman, Francesca Simon, and Charlie Higson.
The competition links to the national curriculum in English, language and literacy across all four home nations, helping pupils to enjoy and create stories, discuss and plan their ideas for writing, use language and structure to engage their readers, and think about the audience and purpose – among other curriculum requirements.
The 50 shortlisted finalists will each receive a £20 national book token, while the gold, silver and bronze winners in both age categories will win themselves a bundle of books. The gold winners' schools will also receive 500 books each for their school library.
The stories, once written by the children, must be submitted (in typed format) by a teacher or other adult using the entry form on the 500 Words website.
- The deadline for entries is 9pm on Friday, November 8. Full details can be found via www.bbc.co.uk/teach/500-words