1.How to Clean Water

You can clean water by filtration.  This is how it works.

You Need

A large clear plastic bottle, cotton wool, sand, small stones and stones that are about 2cms in diameter and a jug of dirty water.

What You Do

Get an adult to cut the bottle about one third from the top.  Put cotton wool firmly in the neck of the bottle.  This part will be the filter.  Add about 4cms of sand, 4cms of stones and larger stones on top of the cotton wool.  Put the filter into the bottom half of the bottle. Then pour in the dirty water.

Pour sand into the top of the bottle on top of the cotton wool.  This will be the filter.

Pour stones on top of the sand.

Put the filter on top of the rest of the bottle and pour dirty water into the filter

What Happens?

The dirty water flows through the filter and comes out clean.  

Clean water

2. I proved that oil is not as dense as water.

by Jennifer

What you need. 

Some water in a bowl and a teaspoon of oil.

What I did

I poured the teaspoon of oil into the bowl of water.

What happened

The oil made bubbles on the surface of the water.  It looked like jelly.  The oil and water did not mix.  The oil floated to the top of the water because it is less dense than the water.