on population, surface area and density. Designed to stimulate children's observational skills, these activity and educational guides make learning fun and more enjoyable. Each I-Spy Guide is arranged in thematic colour-coded sections, to help your I-Spying activity featuring: - Many colour photos and illustration - A short and lively factual description about each entry, with tips on where best to I-Spy. - Points to score Every time you score 1000 points in an I-Spy book, you can apply for a certificate to celebrate your achievement!