National Science Week is an annual celebration of science and technology held every August. You can get your kids involved in several online events, virtual tours and competitions held over the course of the week.

Science is an important part of a child’s learning to help them to discover new ideas and assist their intellectual development. It’s a great way for them to learn skills for everyday life, as everything we do and deal with revolves around science – from cooking, playing sports to understanding different technologies.

To help celebrate National Science Week, we’ve created a selection of easy and fun-filled science experiments that you can do with your kids at home.

Milk and detergent experiment

You will need:

Milk, detergent, cotton buds, shallow plastic plate and coloured food dye.

Method:

1. Pour some milk into a shallow dish until the milk covers the bottom.
2. Add some drops of food colouring to the milk.
3. Add a drop of detergent on the tip of a cotton bud.
4. Dip the cotton bud into the dye and swirl through the milk.
5. Watch in amazement as the colours dance across the surface of the milk.

How does the experiment work?

When the detergent touches the milk, the negative end of the detergent molecules line up with the positive end of the water molecules. This causes the detergent molecules to repel and to zoom out in every direction over the surface of the milk, pushing the food colouring out towards the edge of the plate.

M&M rainbow experiment

You will need:

M&Ms, shallow plastic plate, icy cold water.

Method:

1. Arrange the M&Ms in a circle near the edge of the plastic plate.
2. Fill up a cup of icy cold water. Tip: Pour water into a cup and add ice to cool.
3. Remove the ice when the water is cold enough and slowly pour into the middle of the plate. Make sure the water doesn’t fully cover the M&Ms.
4. Watch the colours disperse into a cool pattern on the plate. This may take a few minutes.

How does the experiment work?

When M&Ms are placed in icy water, the sugary outer shell dissolves causing the sugar to move from the M&M to the water. When the sugar shell dissolves and moves from a place of high concentration (the M&M) to a place of low concentration (the water), taking the layer of food dye with it. When more than one M&M is placed onto the plate, the colours don’t mix because the concentration of sugar at the interface is approximately the same.

Skewer through a balloon experiment

You will need:

Balloons, wooden skewers

Method:

1. Blow up a balloon – make sure you don’t blow it up too large. Tie the end of the balloon.
2. Holding the balloon at the tied end, carefully push the wooden skewer through the centre of the darkest part of the top of the balloon through to the tied end of the balloon at the bottom.

How does the experiment work?

Blowing up a balloon stretches and weakens its skin. Normally when a balloon’s skin is too stretched and a sharp object comes into contact, it causes the balloon to pop.

Balloons are strongest at the very top and bottom because the skin isn’t stretched and is still quite thick, balloon is less inclined to pop at these points as the skin is thicker.

Chain fountain experiment

You will need:

Beaker, metal blind chain (make sure the length is no less than 15m).

Method:

1. Stand in an elevated spot – on a balcony or on a staircase. This experiment is best done when high up.
2. Ensure the chain is placed in the beaker untangled. You will need to feed the chain in carefully to ensure there are no kinks or knots.
3. Place the tip of the chain outside of the beaker and hold over the elevated edge. The chain will then fall.
4. Watch and see how high your chain reaches.

How does the experiment work?

The length of chain outside the beaker is being pulled downwards by gravity. As it is being pulled downwards it pulls on the rest of the chain, slowly unspooling it. Each link of the chain is being pulled around by the links on either side of it.

As a link of the chain is first pulled upwards from inside the beaker, it rotates and applies a force down against the beaker – the beaker in turns pushes the chain up, giving it a ‘kick’ that causes it to arc high in the air as it leaves the beaker. The higher the chain falls from, the higher it will arc out of the beaker.

Chemical rocket experiment

You will need:

Empty plastic drink bottle, rubber cork, gaffer tape, 4 x pencils, 1 piece of tissue, 150ml Vinegar, 1 tsp bi-carbonate soda, measuring jug and measuring spoons.

Method:

1. This experiment is best conducted outside. To build the rocket, tip the bottle upside down and tape the 4 pencils facing upwards around the bottle. The pencils should act as legs, supporting your bottle to stand on its own.
2. Measure out 150ml of vinegar and carefully pour into the bottle.
3. Take 1 piece of tissue, find the seam and separate it. You only need one side.
4. Measure 1 tsp of bi-carbonate soda and place in the middle of the tissue.
5. Fold the tissue over, creating a little parcel. This should be small enough to fit into the bottle.
6. Quickly place the bi-carbonate soda in the bottle and plug with the rubber cork
7. Step about 3m away and watch your rocket take off!

How does the experiment work?

Vinegar is acetic acid dissolved in water and baking soda is a base called sodium bicarbonate. Initially, the reaction makes carbonic acid which is unstable. It quickly breaks down into carbon dioxide and water. The gas then rapidly leaves the water creating foam and bubbles along the way.

When you close the bottle with the rubber stopper, you prevent the carbon dioxide from immediately escaping the bottle. This causes a rapid increase of pressure inside the bottle and eventually gets to the point where the rubber stopper can no longer contain the gases, causing it to explode through the opening. As the contents of the bottle shoot downward, the bottle itself shoots upward.