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Easy Outdoor Science Experiments For Kids


Can Rocks Float?
Not all rocks will sink in water.
Not all rocks will sink in water.
©2007 Publications International, Ltd.

Can rocks float? Most rocks drop with a "ker-plop" to the bottom of a stream or a lake, so your answer would probably be a loud "No!"

You might be surprised, then, to find out that not all rocks sink like ... well, a rock. There is a volcanic rock that won't sink when tossed into the drink. In fact, it will float and bob at the top. Don't believe it? Check it out.

What You'll Need: ­

  • Pumice
  • Bucket or bowl of water

How to Find Out: "Can Rocks Float?"

Step 1: Pumice is created by volcanic activity. It looks different from other rocks and even feels light when you hold it in your hand, but it's a genuine rock.

Step 2: Drop your pumice in a bucket filled with water.

Step 3: Try to sink your rock -- you won't be able to keep it down. It will float!

Another kind of rock that is fun to collect actually comes from outer space. Keep reading to learn how you can find it.

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