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    Make your own salt volcano

    You need:

    A glass jar or clear drinkingglass

    Vegetable oil Salt Water Food colouring (if you want)

    What to do:

    Pour about 8 cm of water into the jar.

    Pour about 1/3 cup of vegetable oil into the jar. When everything

    settles, is the oil on top of the water or underneath it?

    If you want, add one drop of food colouring to the jar. What

    happens? Is the drop in the oil or in the water? Does the colour

    spread?

    Shake salt on top of the oil while you count slowly to 5. Wow!

    What happens to the food colouring? What happens to the salt?

    Add more salt to keep the action going for as long as you want.

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    Hoopster What do I need?

    scissors ruler clear plastic tape plastic straws (not the kind that

    bends) 3x5-inch file cards (or a file folder

    or some other stiff paper)

    What do I do?

    Cut a file card into three equal strips that are 1 inchwide and 5 inches long.

    Put a piece of tape on the end of one strip. Curl thepaper into a little hoop and tape the ends together.

    Put the other strips end to end and tape themtogether.

    Put one end of a straw onto the middle of a strip oftape. Put the big hoop on top of the straw and foldthe tape up the sides of the hoop.

    Put another strip of tape at the other end of thestraw. Press the small hoop very gently onto thetape. Move it around until it lines up with the bighoop, then press the tape down firmly.

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    Hold the Hoopster in the middle of the straw, withthe little hoop in front. Throw it like a spear. It maytake a little practice, but once you get the hang of

    it, your Hoopster will really fly!

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    Why does ice cream melt?

    Ice cream has ice crystals in it. Thatis whats frozen. Things exist indifferent phases, solid, liquid, or gas,depending on their temperature.What you know as ice cream is simplythe solid phase. When the icecrystals melt, the ice cream turns liquidy!

    Why do people put fruit in paper bags?

    It helps to ripen them. Fruit gives off ethylenegas, which is involved in ripening. Putting the fruitin a bag keeps the ethylene a little bit closer tothe fruit than leaving it out in the open.

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    Do eyes grow?

    Your eyes do grow as youage, but only a little bit. Thisis why babies have such bigeyes. The rest of theirbodies is much smaller thana full grown adult, but their

    eyes are about the same size. So as you grow, your face and body get much bigger to catch upwith your eyes.

    Why are carrots goodfor your eyes?

    Carrots contain vitamin A,which you need for all sorts of body tissuefunctions. One of these is the formation of eyepigments involved in good night vision. Leafygreen vegetables and deep orange vegetables areother foods rich in vitamin A.