Explore our World CLIL Readers are graded readers from levels 1-6. They cover a range of subjects and themes, promoting Content and Language Integrated Learning (CLIL). .Animal Camouflage (Science) explores the amazing ways animals are able to disguise themselves in order to survive. .•What colour are many arctic animals? .•How can a caterpillar scare a bird? .•Which spider has got a clever hiding place? .