What Causes Seasons?
Vocabulary
orbit
axis
tilt
equator
seasons

Objectives
Students will be able to explain what causes seasons to change.
Students will be able to identify physical changes caused by the seasons.

Background

The seasons occur because the earth's axis is tilted as the earth orbits around the sun. The north end of the axis points in the same direction almost directly to the North Star. On June 21 the Northrn Hemisphere is tilted toward the sun. This is when the Northern Hemisphere receives its maximum radiation. Dec. 21 the Southern Hemisphere is tilted toward the sun. The Northern Hemisphere receives its minimum radiation from the sun. This is the start of winter in the Northern Hemisphere and the start of summer in the Southern Hemisphere. Seasons Movie from BrainPop

Activities

1.Use a globe and a lamp without a shade to demonstrate how the sun shines on the earth. Have one student take the globe and slowly circle around the lamp, spinning the globe slowly as he moves. Have the student stop at different points during orbit. On each stop have the student tell which portiion of the earth would be warmer, which would be colder. Explain that this is what causes the seasons.

2. The Tilt of the Earth (sung to the tune of Mary Had a Little Lamb)

Earth's tilt makes the seasons change,
Season's change, seasons change,
Earth's tilt makes the seasons change,
They change all through the year.

Near the sun it's summertime,
Summertime, summertime,
Near the sun it's summertime,
The days are hot and bright

Far away it's wintertime,
Wintertime, wintertime,
Far away its wintertime,
The days are cold and gray.

Spring and fall are in=between,
In-between, in-between,
Spring and fall are in-between,
The days are cool or warm.

3. Explain that often you can tell what season it is by looking around. Ask the students to give an example of activities they would do during each season and the clothes they would wear. Have students find pictures in magazines that remind them of a specific season. Create a bulletin board divided into four sections, one for each season. The students will cut out their pictures and place them in the proper section of the bulletin board. Discuss choices.