Wind. There is a lot of it about at the moment and although it can be annoying it can also be put to good use. I did this activity with M and didn’t think it was going to work as well as it did, or at least thought it would take a few attempts to get it to be good. However she loved it so much she wanted to make more, including her own mini windmill!

What you need:

• Card (essential – can be stuff dug out of the good ol’ recycling box)
• Sharp pencil (essential – or something sharp to make a hole, a pencil is about the right size)
• Straw (essential)
• Cardboard tube (essential – you can make this from a rolled up piece of card)
• String (essential)
• Blu tak (not essential, but mighty useful!)

What to do:

• Cut a large square out of your card and then use a pencil to split this into 4 squares.
• Cut in about half way, half way down each side.
• Fold in four parts, one on each side of the square, to make the sails (see photo). The easiest way to do this is fold one and then turn the card 90 degrees and fold exactly how you did before until you have done them all. This way the sails are all facing the same way.
• Pierce a hole in the middle with the sharp pencil and push the straw through. You want this to be a snug fit ideally.
• Pierce two holes in the top of the tube a couple of cm from the top. These need to be in line with each other so you can feed the straw through.
• Blow against the sails and watch the windmill spin round.

Tips/extra bits:

• If your card isn’t snug on the straw then you can use some sellotape to attach it to the back.
• You can tie a piece of string around the end of the straw and something light on the other end (we used a father christmas rubber!). When you blow the windmill the item gets pulled up. Great visual example of how wind power can be used.
• Use blu tank to secure the bottom of the tube to the table so it doesn’t fall over when you blow.

The science bit

Wind. Love it or hate it, it can be very useful. As the air pushes against the sails of the windmill it causes it to turn. Attach the windmill to a shaft and millstone, and you can use the wind power to grind grains of wheat, like in a traditional windmill. Attach it to a pole and pulley, and the wind power can be used to lift objects up. Finally in the case of wind turbines the wind’s kinetic energy is converted into electrical energy, helping to power our homes and cities. This kind of renewable energy is important for the reduction of fossil fuels.

Explaining it to children

It’s a nice visual one where you can see how blowing the windmill turns the sails. Attaching the string and visually seeing something being pulled up demonstrates how wind power could be used in real life to lift heavy objects. You can talk about old fashioned windmills for making bread (think The Little Red Hen story, which talks about making bread from grain), or even visit some. Wind farms are popping up all over the place and so you can explain to your child how the energy from the wind (which you can feel when it blows!) gets turned into electricity inside the wind turbines. This electricity is then used by us in our homes.

Experiment based on an activity from the fantastic Usborne Activities: 365 Science Activities book.