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Turning


Well, let's have a look at doing some simple turning.
Here's something to do at the computer, or you can make a similar thing from card (see the Notes Section ).

Full Screen Version
This text is usually replaced by the Flash movie.

Use your mouse to move the green or red part of the discs. Can you make a turning that shows what:
a) a book being opened looks like from above?
b) turning a volume knob on your music player looks like?
c) a bicycle wheel looks like when going along?
d) a door would look like from above as it's being opened?
e) what a hamster wheel looks like when the hamster's running inside it?

Describe and then show some other things that you do or have seen, that turn in this way.

You can also have challenges that are just to do with the picture you see, for example, can you make the turning shape appear on the other side?
OppCircles
Can you make the red part twice the size of the green?
 
Have fun! You're experiencing Angles - the way turning is measured.

Why do this problem?

This investigation allows children to experiment with turning - they would not need any prior experience to have a go at the activities. The interactivity is a tool for helping pupils develop the concept of turning and can be used before moving on to angle work.

Possible approach

Show the class how the interactivity works (whether you are using the computer-based version or the card version detailed below) by manipulating it as they watch, talking through what you are doing.

You might want to continue by encouraging children to visualise one of the scenarios. Can someone use the interactivity to show the turning they had been imagining? Invite the rest of the group to comment and refine the motion accordingly. You could then actually find the article and do what is described to see how accurate the interactivity was.

Children could then work in pairs, either at a computer, or with the card version. Encourage them to talk to each other as they try out their ideas.

Key questions

Tell me about what you are imagining.
How could we "check" what you have done?

Possible extension

Children could demonstrate a turn and challenge other children to select what it represents from, for example, a list of three scenarios.

Possible support

To make a version of this interactivity which does not require technology, we just need two differently-coloured discs of thick paper or card. A slit is cut into each from the edge to the centre in a straight line. The two slots are then allowed to overlap each other and turning links the two together.

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