Many left their normal school uniforms at home on Thursday, March 6 and instead dressed up for the day as characters from their favourite books.
Photographer Tony Hendron took these great pictures when he popped into St John The Baptist Primary School / Bunscoil Eoin Baiste, Ballyoran Primary School, Hart Memorial Primary School and Millington Primary School.
We also asked our readers to share photos of their children dressed up in their fun costumes and we were delighted with the response. Thanks to all who shared their pictures with us.

29. World Book Day
Arwen as Maleficent, Dante as Iron Spider (Spiderman) Photo: Sarah Willis

30. World Book Day
"Penny's theme was nursery rhymes. She picked 'I’m a little teapot'." Photo: Kylie McCully

31. World Book Day
Jack (4) all dressed up as Captain America. Photo: Rebecca Clark

32. World Book Day
Samuel as Billionaire Boy. Photo: Ruth Boyes

