Does water make you wonder? -- How much water is there on Earth? -- Why does it rain? -- Is there water underground? -- How do rivers form? -- How are rainbows and water related? -- What are lakes? -- How is a sea different from an ocean? -- How is an ocean different from a sea? -- Why are the seas and the oceans salty? -- Why are the seas and the oceans blue? -- Who are the involuntary travelers in our oceans? -- What lives in our oceans? -- What's on the water's surface? -- What's on the shore? -- How powerful is water? -- What are tides? -- What causes flooding? -- What is life without water? -- How did people get water in ancient times? -- Where does the water in your tea come from? -- What about water in cities? -- Water: inside and outside? -- What do humans think about water's mysteries? -- How can we protect our planet's water? -- What can you do to protect nature and yourself?