"Once Upon a Time..." is a children's book that addresses a variety of critical environmental issues. It has been specifically designed for young readers and provides scientifically grounded information in an understandable language. The combination of engaging texts and numerous images facilitates the understanding of complex topics and promotes awareness of environmental issues. This book is ideal for children and teenagers who want to learn in an entertaining way how they can contribute to the preservation of the environment. Its appealing design and child-friendly presentation make it a valuable companion for young explorers.