This is a great question because it’s so easy to demonstrate, all you need is a ball and a light, preferably a lamp or torch.
Firstly it helps if they have an idea that the earth is a sphere. If they’ve travelled a bit it’s great, you can show them on the ball where they’ve been. We’ve just got back from holidays, so I chose one point on the ball for home and we discussed flying around the other side to England.
- Make sure there is a point on the ball they can identify, either something already there or draw a spot. Tell them that the earth is like a ball, and they are standing on the spot. If they know something about maps, countries or cities you can draw them on as well to help them visualise it.
- Hold it in front of the light so they can see the clear line between the light and dark sides. You may need to turn off the room lights or shut the curtains. Have the dot that’s them in the light section.
- Tell them it’s day for them, then slowly turn the ball like the earth does. Have them follow the dot and point out when it’s sunset, then night then sunrise and day again. We went through this several time, with big girl excitedly yelling “Day!” and “Night!”
- For older kids, you could even introduce the year and seasons if you want!
Big girl is 4 and asked the question. Do I think she’s got it? No, but it’s an introduction. One of the biggest things science teachers do in school is deconstruction. All people have developed ideas about how the world works just through living. The way our brains work, we don’t replace these ideas until they become too uncomfortable, even if it means we have contradictions.
Example: I’ve taught teenagers who ‘know’ that the earth goes around the sun. But then on a test they’ll pick an answer like “the sun and moon are on opposite sides of the earth,” which shows they haven’t internalised it.
This is a fairly trivial example, but having a false world view can stop you asking the right questions – we wouldn’t have reached the moon if we didn’t realise it was big enough to visit.
Science teachers spend a lot of time trying to identify false ideas and correct them. There are two things needed to deal with false ideas:
- Make them explicit, most of us don’t realise we have them until they’re challenged in an unexpected way.
- Repeat the real ideas often in as many different ways as you can.
The earlier you do it the better, because you might even stop the false ideas forming in the first place. So a toddler is not going to understand day and night from one time of playing with a ball. But it is one little thing that can help add up to an accurate world view.
Enjoy this article? Subscribe to the weekly newsletter to hear about them all. Or grab my RSS feed