“Just wait 10 minutes!”



How many times have you heard that? Quite a few I'd imagine when you are impatiently waiting to go out and your parents are still getting ready.


Make the Science clock and time your parent, brother or friend to see just how long it takes them to do something.


(This is a useful experiment for younger children who cannot tell the time or do not yet have the concept of how long 5 or 10 minutes actually are. It is also a lot of fun for older children who are curious as to how long certain activities take to complete.


You will need:

Two paper cups                     A ruler or a thin piece of wood

Modeling clay                        A drawing pin

A watch                                 Water



The Experiment

(1) Carefully make a small hole the bottom of one of the cups with the drawing pin.

(2) Attach the cup to the top of a ruler (or thin piece of wood) with some tape

(3)  Tape the other cup without a hole, to the ruler, underneath the first cup.

(4)  Stand the ruler upright (You may need to secure it with modeling clay or plasticine)

(5)  Cover the hole in the top cup with your finger and fill it with water

(6) When you take your finger away the water should start to drip into the bottom cup

(7) Time the drips with a watch and mark the level of the water in the lower cup every minute and five minutes (You are making a time scale on the bottom cup)

(8) Each time you use this from now on you will be able to tell how much time has passed just by looking in the bottom cup

(9) Try putting a drop or two of food colouring into the bottom cup. This will look like the water changes colour as time passes – COOL!!



Did you know ............


There are two forces acting here. One is the force of the water pushing down into the cup. The other is a force called gravity, which pulls the water down from the top cup to the bottom cup. Gravity is what keeps us on the earth. If there was no gravity then we would be like astronauts on the moon and float around in space.

Next time you take the plug out of the bath or sink , put your hand over the plughole. You can feel the water being pulled down by gravity. Because the plughole is small compared to the amount of water being sucked down, the water spins into a whirlpool as it disappears!


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