Teacher sheet · Ages 10–11 · about 45–50 minutes
Day, night and the reasons for the seasons
Lesson page: echoesof.science/school/day-night-seasons/ages-10-11/ · Pupil worksheet: echoesof.science/school/day-night-seasons/ages-10-11/print/
Learning aims
- Day and night are caused by Earth's rotation (about 24 hours).
- A year is one orbit (365.25 days).
- Seasons are caused by the tilt of Earth's axis: higher Sun and longer days in summer.
- Distance from the Sun does not cause the seasons.
- Carry out a fair test with one changed variable.
Lesson plan
| Time | Activity |
|---|---|
| 5 min | Starter: show the misconception 'summer = closer to the Sun'. Who agrees? |
| 10 min | Read the text. Use a globe and a lamp to show the tilt in June and December. |
| 20 min | Torch fair test in groups, filling in the table. |
| 5 min | Share results: link the slanted torch to winter sunlight. |
| 5 min | Quiz or the Summer or winter? game. |
Materials for the experiment
- A torch
- Squared paper (1 cm squares)
- A ruler
- A protractor
- A pile of books to rest the torch on
- A pencil
Safety: Don't shine the torch into anyone's eyes. Never look at the real Sun, not even through sunglasses.
Common misconceptions
| Pupils may think… | Actually… |
|---|---|
| Earth is closer to the Sun in summer. | Earth is closest in January; the difference is only about 3%. |
| The Sun moves across the sky because it goes around the Earth every day. | The daily movement is caused by Earth's spin. |
| The tilt of the Earth changes during the year. | The tilt stays about the same; as Earth orbits, first one hemisphere and then the other leans towards the Sun. |
Worksheet answers
- Earth spins on its axis once in about 24 hours; the half facing the Sun has day and the half facing away has night.
- The Sun is higher, so its light is more direct and concentrated; and the days are longer.
- Earth is closest to the Sun in January, when it is winter in the north; the distance changes by only about 3%; and the two hemispheres have opposite seasons at the same distance.
- Changed: the angle. Kept the same: torch, distance, paper. Found: at smaller angles the patch was bigger and dimmer.
Quiz answers
- How long does the Earth take to spin round once? About 24 hours. One rotation takes 23.9 hours.[2]
- What causes the seasons? The tilt of Earth's axis. The tilt makes the Sun's rays more direct in summer.[1][4]
- When is Earth closest to the Sun? In January. About 147 million km in January, northern winter.[1][3]
- Why does slanted sunlight heat the ground less? The same light is spread over a bigger area. Like a tilted torch, the light patch gets bigger and dimmer.[4]
- What is special about an equinox? Day and night are about 12 hours each everywhere. 'Equinox' means 'equal night'.[4][5]
- Why do we have a leap day every four years? An orbit takes 365.25 days, not 365. Four extra quarter days add up to one day.[2]
Going further
Look up today's sunrise and sunset times and work out the length of the day. Do it again in a month. Is the day getting longer or shorter? Why?
Sources used in this lesson
- [1] What Causes the Seasons? (NASA Space Place): reliability High
- [2] Earth: Facts (NASA Science): reliability High
- [3] Why Does Earth Have Seasons? (NOAA NESDIS (U.S. satellite and information service)): reliability High
- [4] Astronomy, 4.2 The Seasons (OpenStax, Rice University): reliability High
- [5] What is the summer solstice? (Royal Museums Greenwich (Royal Observatory)): reliability High
Full list with links and a note on each source's reliability: echoesof.science/school/day-night-seasons/sources/
Privacy: the lesson pages have no ads, no tracking and no cookies. Quiz answers and game scores stay in the pupil's browser. A short video for each age is coming.