The Sun Does What?
By Shannon Lewis, October 5, 2009
- Elementary School
- collect data
- analyze data
- understand how shadows are made
- understand how shadows change in response to the sun or light sources position to an object
- understand how the sun’s position changes in the daytime
- communicate and collaborate in small groups
- design a tool that can be used to demonstrate that the sun changes position in the sky during the day
- axis: the line about which a rotating body, such as the earth, turns
- rotate: to cause to turn around an axis or center point; revolve
- shadow: a dark figure or image cast on the ground or some surface by a body intercepting light
Day 1: Introduction -- The purpose of this introduction will be to discuss and chart students’ prior knowledge of the sun and day and night. This can be taught a day prior to the lesson activities or the morning of the same day.
- What causes daytime?
- Where does the light come from?
- Where is the sun in the morning, noon, evening?
- Is the sun always in the same position? How do you know?
- What is a shadow?
- How is a shadow created?
Students should be told that Earth rotates once on its axis in a 24-hour period if they do not share this knowledge during the discussion.
Steps for Learning: The purpose of these activities will be for students to make discoveries and generalizations about the sun, shadows, and shadows' relationship to time of day.
1. Tell students that they will be working in groups of three to four to observe their shadows at different times of the day.
2. Divide the class into groups of three or four students. Keeping in mind language levels and academic abilities. These students will work together during the course of this lesson.
3. Hand out the recording sheets, pencils, and one piece of chalk per group.
4. Take class outside on a sunny day first thing in the morning to a flat concrete or black top surface.
5. One student in the group will face south while another student traces that student’s shadow with sidewalk chalk. Allow each student in the group to have an opportunity to have his/her shadow traced.
6. Students will then use a yardstick to measure the length of their shadow.
7. Students will note length, time of day, and position of their shadow on the ground and on their paper.
8. Bring students back into the classroom to briefly discuss findings. Explain that they will repeat this procedure two more times during the day, once at midday and once at the end. (Be sure that students stand in the same place each time.)
Day 2: Designing
1. Allow students to discuss in their groups the data they collected, any patterns they discern, and reasons why they think patterns emerged.
2. Ask the groups to gather in a whole group meeting area to share their findings.
3. Write their ideas and findings on chart paper for future reference.
4. Present design challenge:
- Explain to students that they are being challenged to design something that could be used to prove that the sun’s position changes in the sky as time changes. The activity they completed the day before with their shadows is one way to prove this, but they are going to come up with an entirely new idea.
- They will work in their same groups to complete the challenge.
5. Work Time
- Present students with the materials they will be able to use to make the device. (Explain that they do not need to use all of materials in their design.)
- With students in their groups, they will brainstorm design ideas.
They will write, sketch or model ideas on a large sheet of paper. (Emphasize teamwork: listening to each person’s ideas, sharing the work, and taking turns.)
Reinforce that all ideas in a brainstorm are great ideas and that brainstorm ideas do not have to be practical or doable.
6. Gather students to whole group meeting area to share a couple of ideas with the class.
7. Give each group a “Design Idea” handout to complete once they have decided one design to pursue. This will give the group an opportunity to plan and reflect on their plan before beginning.
8. Let the designing begin.
9. Have flashlights available for students to test their devices throughout the work time. Explain that the light bulb in the flashlight can act as the sun.
10. At the end of the class period, tell students they will have thirty more minutes during the next class period to finish their device.
Day 3: Testing/Sharing
1. Give students about thirty more minutes to test out their devices and make adjustments. Remind them that their objective is for their device to prove that the sun’s position changes in the sky.
2. When groups feel they have successfully created their device have them fill out the “Sun Does What? Design Challenge” self-evaluation.
3. Student groups will present their devices to their peers, explaining the how they created it and how it can be used to prove that the sun changes position.
Have classroom lights off and flashlight available to demonstrate effectiveness of the creation or take students outside if the weather is permitting.
4. If groups find that their design needs some changes, give them times at the end of the period to redesign and present their changes.