These photos were submitted by parents across Sheffield, offering a glimpse of how children marked the annual celebration of reading.
From the many photos sent in, we’ve chosen 60 of the most dedicated, hilarious and creative outfits.
Unsurprisingly, some classic characters appeared more than once. There were plenty of young witches and wizards representing Harry Potter, complete with round glasses, striped scarves and carefully drawn lightning-bolt scars.
Julia Donaldson favourites were also popular, including charming versions of Stick Man and a brilliantly simple but effective Runaway Pea.
Eric Carle’s much-loved Hungry Caterpillar wriggled its way into several classrooms, while Dr Seuss fans brought the chaos with energetic pairs dressed as Thing One and Thing Two.
One pupil even channelled their inner chocolate factory villain as Veruca Salt.
But World Book Day is always at its best when pupils dig into the more unusual corners of their bookshelves.
Alongside the well-known characters were some wonderfully unexpected choices - from lesser-known fantasy figures to inventive homemade costumes that clearly took plenty of imagination (and a bit of cardboard).
These 60 costumes stood out from the photos sent in from across Sheffield:
