Students should have an emerging understanding of the
concepts of rotation (spin) and revolution (orbit) after completing
the "The Motion of the Sun and Earth: Using a Playground
Model to Explore Rotation and Revolution" lesson.
balls: (6-inch ball for the Sun, 3-inch ball for Earth)
disk: (8-inch round x 2-inch thick) for base to hold Sun
ball (Note: The relative sizes and distances of materials
used in this model are not the actual scale of the Sun-Earth
bamboo skewers (1214 inches)
Lamp with 200 watt bulb with shade removed to serve as the
Extension cord for lamp
Allow 15 minutes to locate
and prepare materials.
will learn that:
Sun is at the center of the solar system.
Sun rotates or spins on its axis.
Earth rotates or spins on its axis.
Earth rotates and revolves around the Sun.
takes one year for the Earth to complete its orbit around
In the classroom
a location in the classroom with ample room (approximately
10x10) to demonstrate the Sun-Earth model. Students
may want to sit in a circle or semi-circle with the model
in the middle.
not using the lamp, insert one end of one skewer into one
6 inch ball and the other end of the skewer into the Styrofoam
disk to elevate and secure the ball (see
Styrofoam 6-inch ball (or lamp) where all students can see
that the large ball or lamp represents the Sun. Ask students
what they know about the Sun and write answers on the board
or KWL chart. Possible points to elicit:
that the Sun spins in the center of the solar system and
that the planets are always orbiting around it. The Sun's
position is like the hub of a bicycle wheel, with planets
spinning around it counterclockwise. Note: If using a
lamp, turn it on and turn the classroom lights off to crate
a light emitting "Sun."
a 3" ball on a bamboo skewer to represent the Earth.
Hold the skewer vertically so that the Earth can be held
from above and rotated (see
example). Explain that the Earth spins counterclockwise,
and that it is smaller than the Sun. Note: Stress to
students that the Sun-Earth model is not to correct
scale. Explain that distances in space are vast, but
that this is a model to help see the big picture.
the Earth orbiting around the Sun. Start by walking counterclockwise
in a circle around the Sun (approximately 4 feet away from
the Sun ball or lamp at the center). Turn the skewer counterclockwise
to demonstrate the Earths spin, while orbiting the
Sun. Ask students to identify both kinds of motion: rotation
students how long it takes for the Earth to revolve all
the way around the Sun. To make this concept easier to grasp,
choose a point on the Earths line of orbit. Explain
that if the Sun were at this point on the first day of this
school year, it would take the entire yearfall, winter,
spring, summer and back to fall when the next school year
startsfor the Earth to complete its long trip around
a student when his/her birthday is and how old he/she is.
Model a complete orbit of the Earth and ask how old he/she
would be after the Earth revolves around the Sun. Ask several
students in your class how many times the Earth has revolved
around the Sun since they were born?
our closest star
at the center of the solar system
slowly compared to the Earth
counterclockwise when seen from above with North being
huge (much bigger than Earth!)
our light source
Ask the students to model the movement
of the Earth around the Sun for the whole class.
related books and websites.