Days and Nights

Let us explain days and nights to kids sometime. By the time the children are four year old, they mostly understand when is the morning, noon, evening and night.

Why is it morning now ? "Because the there is light" .
Where does the light come from "From the sun".
What happens in the night " The sun goes away".
But where does it go ?

Step 1 - Learn about the Earth
I love to explain this to Dhanya with a globe. We first started off by familiarizing her with the fact that the globe is in fact the Earth. And we all live in the Earth.

Many schools teach simple rhymes about the contents . Here is one I found on the web.

The 7 Continents
North America, South America, joined in the West
Europe meets with Asia, and on Africa they rest.
Australia stands alone, floating down below
And Antarctica is the loneliest, where no one want to go.

Since she already knew a rhyme about all the continents, I showed her where each continent lies on the globe. Then, We tried to relate these continents to real world people.
' Father has gone to USA. Here is the USA in North America continent.'
' My sister lives in Australia. Australia is here in my globe.'
'All the blue colour in the globe are vast oceans'.

Step 2 - Learn about the rotations and revolution
It is good to show the kids how the rotation and the revolution of earth happens before proceeding to talk about days and nights.  As I mentioned elsewhere, long back when these concepts were explained to me in school, Our science teacher put a chair in the middle of the class - Asked us to assume it to be the sun and went around it as the earth would, showing us rotation and resolution. It is good to do this exercise with the kids.

Step 3 - Learn about the days and nights on Earth
Once the child is familiar with the rotation and revolution, We need ,

• A globe
• A torch
• A darkened room

The globe is the earth and the  torch is the sun.  Now, Make the earth move around the sun.  We should slowly rotate the earth first. Point to the child how there is sun light in one part of the earth and it is dark in the other part.

It is a nice exercise to repeat this experiment several times, probably once every two weeks. The child's understanding of the concept of day and night strengtens.

• Point to various parts of the globe and ask if it would be day or night there.
• Encourage the kids to talk to friends and relatives in various parts of the globe. The child could ask the friend if it is day or night there and can further cross check with the globe. They could even show them if it is day or night outside on a video chat.

Some advanced topics to cover -

• Why do we have various seasons ?
• Why is the size of the moon different on different days ?

About Lights and Shadows

One fine evening when the sun had set and the street lights were switched on, Dhanya and I were going out for a walk to a shop nearby.
'Amma, Look there is another girl there' She exclaimed to me pointing to her shadow.
'Oh ! That is your shadow' I said.

Now questions started pouring in about shadows. I decided to explain to her in detail. But it is a bit tricky in the streets. Where are multiple sources for lights and hence multiple shadows. And these shadows all have varying sizes.

Its much easier when you go out for a walk around the noon time on a sunny day. There is only one major light source - the sun.  Here is how I explained to her.

When light falls on an you and the light cannot pass through you. You are blocking the light. You are stopping it from moving further. Hence no light reaches in front of you from behind you. Hence that area is dark as there is no light and it is your shadow.

So, We went home and picked up three different objects -

1. An opaque object - A wooden block.
2. A transparent object - A glass (plain class) of clear water
3. A translucent object - A translucent paper ( sort of semi - transparent)

We put off the lights, drew the curtains  and darkened the room. We then used a clear light source ( a candle ) and used the three objects to cast clear shadows on a plain wall.

A candle casting a shadow on a wall - Image by Paolo Neo

Now, She was able to understand the whole concept of light getting blocked. She also understood different types of objects and how you could see through some ( like glass ) and how some do not.

We also observed the kind of dark shadow caused by the wood against the light one caused by the paper.

We can use a pencil and a paper to draw how light travels from the sun, how We obscure that path and how the shadow gets formed on the ground below us.

Shadow caused by the sun.

Now, going back to the streets again,  Here are some more things to observe.

Multiple Shadows due to different light sources

• When there are multiple street lamps, walking between them causes multiple shadow.

• When we moved closer to the street lamp our shadows become smaller.  It is the smallest right under the street lamp. As we move away from the street lamp, the shadows tend to grow.

This can help the child learn that the distance between the light and the object  decide the length of the shadow. Of course,  Dhanya did  not get  it all. However, I am sure she will learn to observe more and possibly draw her own inferences.

This is a brilliant topic to discuss with kids during walks when the sun is out. The concepts can be explained slowly over a period of time gradually increasing the complexity. F

Advances topics related to shadows -

•  The size of the shadow caused by the sun in the morning, noon and evening. This will vary depending on the time of the day.
• Eclipses are nothing but shadows caused by heavenly objects.
• Learning to find the length of the shadow. Use a paper to position the sun at various places . Make the child draw straight lines from the sun to guess the size of the shadow. ( as shown above.)

• Learn more about shadows here - http://www.learnnc.org/lp/editions/earth-sun/6624

Reading with kids

We happened to pick up a book on solar system one day from our neighborhood library. The book had several pictures of the planets, the sun, the moon and comets. It explained through pictures how the earth and the moon revolve and rotate about their axis. Long back when these concepts were explained to me in school, Our science teacher put a chair in the middle of the class - Asked us to assume it to be the sun and went around it as the earth would showing us rotation and resolution. We did the same exercise with my daughter. It was a hit !!!

I started to look for simple books for 3-5 year olds. With lots of pictures and a little bit of description. That is when I stumbled upon the  Big and Busy Priddy Books.

This series is ideal for 3-5 year old kids - Lots of lucid, bright pictures to kindle their curiosity. Flaps and wheels makes every page interesting and entertaining for the children. We have so far purchased the following two books and have found both very very useful.


Some topics which we really enjoyed reading are - A page on optical illusions and the digestion process explained with tiny little flaps in the Body book.

Other books in this series which are interesting -