A screw was invented by Archimedes.

A screw is also an inclined plane.
An inclined plane is usually used to move something.
Archimedes's screw is lifting water to water the fields.

Let's make a screw hoist.

You need: a big bowl with popcorn, a smaller empty bowl,a plastic bottle scissors, some cardboard,tape, a stick, and a box.

1. Cut a tube from the bottle
2. Draw 6 circles with the help of the tube to the cardboard.
3. Draw centres to the cardboard circles.
4. Cut out the circles.
5. Use a tape nad make a screw.
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6. Jab a hole through the circles.
7. Put one tip into the big bowl.
8. Put a smaller bowl on the box and the other tip of the screw into it.
9. Turn the screw.What happens?
10 .What happens if you turn backwards?
11. Do you know machines that work like that?
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