We all want our children to grow up smart, sensible, successful, empathetic and, of course, happy. But if education in the natural sciences is more or less organized at school, then what about the rest of the knowledge and skills? This book will answer the most important questions and help parents develop 21st century skills in their teenager. In particular, here you will find information about: self-organization, systemic, creative and critical thinking and how to help your teenager develop it. Caring parents will find clues in this book for all cases when complex things need to be explained to a teenager simply and easily. This is a training book, so there are a lot of exercises and simulators in it. Use them, they work. Cheers!