Colourful, surprising and full of information the I Wonder Why books have set thousands of young minds buzzing. I Wonder Why Zips Have Teeth is the perfect introduction to inventions, featuring the first computers, robots on Mars, ebook readers and much more.What do you want to find out? Clear, lively text answers all those tricky questions about how the world works while friendly, funny cartoons add interest. With more than 35 titles across a mind-expanding range of subjects, this is a series guaranteed to amaze and amuse.