Charles is a children's picture book author. He has written a number of titles for Wild Dog Books across a range of series. These include Our Past, Extreme Weather, Going Supernova, Then and Now, Australian Animals, Continents of the World and CloseUp. He has also written numerous one-off titles such as Hunters & Hunted, Fantastic Facts, Gross Facts, The Book of the Sun and the Stars, The Big Book of Antarctica and The Big Book of the Bicycle.