Simple Technology: Wheels

Liz Lennon is a writer who specialises in children's non-fiction. She lives in Hertfordshire with her husband and young daughter, who is the best critic of her mum's work. Ellie is a coffee addict, an avid snowboarder and bad joke-teller. She completed her degree in Illustration in Plymouth and now lives in Worcester with her (equally bad joke-telling) boyfriend. They both love lazy Sundays watching cartoons all day, Ellie's biggest inspiration for drawing! She has always loved watching cartoons and when she was around 8 she decided, "Hey, I want to draw like that!" So she picked up her pencil, and here we are. Ellie loves writing and illustrating children's books, starting with scribbles before drawing and colouring up in Illustrator and Photoshop. When she's not doodling or drinking coffee, you will usually find her shopping for makeup, binge-watching cartoons or watching pug videos online. "Yes, I am an adult, why do you ask?"

• 1: What are wheels?1: Wheels and axles1: Moving things1: Different types of wheel1: Turning and steering1: Making a toy car1: Tyres1: Tractor1: Working wheels1: Spinning wheels1: Gears1: Machines with gears1: Wheels and people1: Useful words1: Index