It's hard to believe, but the moon is better explored than the sea. There is still much to discover! At the sea and along the coasts, there are a thousand fascinating things to explore. Why is the sea sometimes there and sometimes gone? How can animals live in the deep sea? How do rocky and steep coasts differ? This book contains many answers to exciting questions. Additionally, it offers plenty of expert knowledge about the sea and coasts, as well as numerous experiments that allow children to become marine researchers themselves. From the content: - Why is Earth called the blue planet? - How did life in the sea originate? - Why is the sea sometimes gone? - Where are the animals in the tidal flats? - How can animals survive in the deep sea? - What swims in the sea and is dangerous? - How do wind and storms form? - How do the coasts of the Baltic Sea, North Sea, Atlantic Ocean, and Mediterranean Sea differ?.