With a couple of stick legs, two lopsided eyes and a blob for a body, their naivety is part of their charm and a poignant reminder of the innocence of childhood.
But one father was so tickled by his two young sons' early attempts at animal drawings that he reimagined them as real-life photographs — with utterly hilarious (if slightly terrifying) results.
Using the editing software Photoshop, Tom Curtis turned the scribblings of sons Dominic and Alistair into a globally successful Instagram account and a hit book.
'I start by almost mapping the photograph on to the drawing,' he explains.
'I never change the drawing because I love the way young children often seem to draw animals with eyes on the same side of the head. I gradually build up the picture like a jigsaw by adding bits of photographs and placing them within the drawing until I have a kind of digital collage.'