Why is there day and night?

As a class, activate prior knowledge by having students share what they already know about night and day.

Use a projection device to share the Day and Night KWL Chart [Google doc] [Word doc] [PDF] on a screen. Ask students to share what they know and record this information in the “Know” part.

Note: Use symbols as well as or instead of words.

If you are unfamiliar with KWL charts, review this page that explains in detail how to use this learning strategy.

Students may need further support for triggering their knowledge. You could do this by showing students a time lapse video of night and day time such as this video or this video.

Alternatively, encourage students to go outside with their trusted adults in the evening and during the day to make some observations.

Discussions

Discussion prompts can include:

• “What are some things you see during the day? What are some things you see at night?”
• “What do you hear during the day? What do you hear during the night?”
• “What are some things you do during the day? What are some things you do at night?”

Show students the slideshow Why is there day and night? [Google slides] [pptx] [PDF]

As a class add student questions and new knowledge and challenge existing ideas on the KWL chart.

Language

Create a word wall with images of terminology students are likely to encounter during this lesson such as Sun, Moon, Earth, axis, turn, spin, etc.

Incorporate vocabulary in other relevant languages as well (e.g., French). Ask students who feel comfortable sharing some of the words they know in the language they speak about night and day.

Using a globe and a flashlight, demonstrate how the Sun shines on the Earth. You will want to do this in a somewhat darkened room.

Encourage students to notice that only one side of the globe is lit by the flashlight. This is the part of the Earth that experiences day. The other side of the globe is in shadow. This is the part of the Earth that experiences night.

Slowly turn to the globe to demonstrate how the Earth rotates like the animation in the slideshow. 

Note: To have students take notice of the rotation, put a sticker or marker on one spot on the globe. It could be where your school is located.

Students should notice how different parts of the Earth pass through the light and shadow. Ask students if they think everyone around the world sees the Sun at the same time. Have them explain why or why not. Shine the light on Australia and ask if people on the opposite side can see the Sun. and ask them if it is night or day there.

To see a demonstration on how to do this watch this video.

Idea

If you do not have access to a globe, you could use a foam ball with a wooden skewer pushed through the centre as an axis.

Discussions

Discussion prompts can include:

• Point to Canada on the globe with the flashlight pointing straight on say to students; “This is where we live. What do you think the people who live on the other side of the globe see when we see the Sun?”
• “At night, if we want to telephone a family member who lives on the other side of the globe will they be going to sleep or waking up?”

Students could consolidate their learning about night and day by participating in the Why is there day and night? Consolidation activity [Google doc] [Word doc] [PDF].

Use a projection device to share the page. You can read the sentences and students could select the correct word or image to fill in the missing word.

Responses for the reproducible include:

• The Sun shines in the day.
• At night we can see the Moon and stars.
• The Earth turns on its axis.
• When the Earth is in shadow it is night.
• It takes 24 hours for the Earth to make one full turn.

If using the [Google jamboard] students can drag and drop the words into the correct places in the sentences. Make a copy of the jamboard before starting.

Alternatively, have a discussion with the class or with individual students using questions such as these:

• What causes night and day?
• When can we see the Sun?
• When do we see the moon?
• At what time of day do we first see the Sun?
• At what time of day do we last see the Sun?
• Does everyone around the world see the Sun at the same time? Explain.

Language

If you are using the reproducible on an interactive whiteboard, students could write or draw images to complete the sentences.

As a class, using a projection device, reflect on the learning and contribute to the “L” section of the KWL chart.