Dial up the Sun! Patterns on Earth and in Space
In this activity, students will work in pairs to design an innovative gnomon for a functional sundial. Students will record data regarding their observations about the length and position of shadows cast by the sun over a series of 4 hours. Based on this data, students will make inferences regarding patterns to predict the length of the shadow and its position over the next 2 hours.
Knowledge
Students have
had practice in measurement in centimeters using a ruler.
had practice in telling time on a digital and/or analog clock.
have had practice in making observations.
had practice in recording data.
had practice in measurement in centimeters using a ruler.
had practice in telling time on a digital and/or analog clock.
have had practice in making observations.
had practice in recording data.
Objectives
Students will
create a stencil for sundial gnomon.
use the 3Doodler to construct a gnomon for a sundial.
observe and identify patterns of shadows cast on their sundials.
understand the purpose of a sundial.
understand that changes in shadows are based on the earth's position in relation to the sun.
understand that the earth's rotation affects the position and length of the shadow cast by their gnomon.
create a stencil for sundial gnomon.
use the 3Doodler to construct a gnomon for a sundial.
observe and identify patterns of shadows cast on their sundials.
understand the purpose of a sundial.
understand that changes in shadows are based on the earth's position in relation to the sun.
understand that the earth's rotation affects the position and length of the shadow cast by their gnomon.
Materials
Students will need
3Doodler (1 per pair)
pencils (3-4 per pair)
white copy paper (1 per pair)
paper plate (1 per per pair)
3Doodler (1 per pair)
pencils (3-4 per pair)
white copy paper (1 per pair)
paper plate (1 per per pair)
Lesson Plan
Instructions
Step 1
Ask: Can you create an accurate sundial to tell time by the hour?
Step 2
Project your computer or tablet screen to display images of traditional sundials from a safe Google search.
Step 3
Ask students to share all they know about sundials. Record their responses.
Step 4
Define the term "gnomon" as the projecting piece on a sundial that display the time by the position of its shadow. Share what attributes the gnomons in the images have in common. (Possible responses: They are triangular blades or sticks.)
Step 5
Share the goal: Students will work in pairs to design an innovative gnomon for a sundial they will use to track the time over the next 4 hours. Their sundial will display the time based on the position of shadows cast by the sun.
Step 6
Share materials: paper plate, paper, pencil and 3Doodler.
Step 7
Ask students to predict if a different shape would work just as well or better as a gnomon.
Step 8
Set base criteria for gnomon: The length of the gnomon should be equal to the radius of the paper plate. Explain that this is the distance from the center of the plate to its edge.
Step 9
Model how to create a stencil / template for an innovative gnomon. Vary its shape.
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Step 10
Use the 3Doodler to trace and fill in your gnomon.
Step 11
Use the 3Doodler to weld your gnomon down to the center of the paper plate.
Step 12
Tape the sundial down in front of a windowsill where it will receive plenty of sunlight.
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Step 13
Trace the shadow of your gnomon using a ruler to draw a straight line from the gnomon to the edge of the plate. Record the time.
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Step 14
For the next 4 hours, have students record the time in the same way. As students work, circle to assist and assess.
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Ask: Can you create an accurate sundial to tell time by the hour?
Project your computer or tablet screen to display images of traditional sundials from a safe Google search.
Ask students to share all they know about sundials. Record their responses.
Define the term "gnomon" as the projecting piece on a sundial that display the time by the position of its shadow. Share what attributes the gnomons in the images have in common. (Possible responses: They are triangular blades or sticks.)
Share the goal: Students will work in pairs to design an innovative gnomon for a sundial they will use to track the time over the next 4 hours. Their sundial will display the time based on the position of shadows cast by the sun.
Share materials: paper plate, paper, pencil and 3Doodler.
Ask students to predict if a different shape would work just as well or better as a gnomon.
Set base criteria for gnomon: The length of the gnomon should be equal to the radius of the paper plate. Explain that this is the distance from the center of the plate to its edge.
Model how to create a stencil / template for an innovative gnomon. Vary its shape.
Use the 3Doodler to trace and fill in your gnomon.
Use the 3Doodler to weld your gnomon down to the center of the paper plate.
Tape the sundial down in front of a windowsill where it will receive plenty of sunlight.
Trace the shadow of your gnomon using a ruler to draw a straight line from the gnomon to the edge of the plate. Record the time.
For the next 4 hours, have students record the time in the same way. As students work, circle to assist and assess.
Wrap Up
Assessment
Possible Extensions
Resources
Possible Discussion Questions:
How does the sundial use Earth's movements to tell time?
How does the angle of the light change the direction of the shadow?
How did the shape of your gnomon affect the size or length the shadow cast?
Is there anything you could do to improve your gnomon?
What is the path of the sun as it moves across the sky?
Do you think that the path of the sun changes throughout the year? Explain.
Vocabulary
gnomon - the projecting piece on a sundial that display the time by the position of its shadow.
Educational Standards
Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 4 topics and texts, building on others' ideas and expressing their own clearly.
Students will share predictions and ideas based on their observations throughout this activity.
Pose and respond to specific questions to clarify or follow up on information, and make comments that contribute to the discussion and link to the remarks of others.
Students will participate in discussions with their partner during this investigation, as well as with the whole group.
Earth's Place in the Universe: Represent data in graphical displays to reveal patterns of daily changes in length and direction of shadows, day and night.
Students will record their observations based on the length and position of the shadow cast by the gnomon over the course of 6 hours.
Plan and create a design document to illustrate thoughts, ideas, and stories in a sequential (step-by-step) manner (e.g., story map, storyboard, sequential graphic organizer).
Students will create sketches and stencils while planning the 3Doodler design of their gnomon.
Decompose (break down) a larger problem into smaller sub-problems with teacher guidance or independently.
Students will break down the process of understanding the purpose of the sundial and the pattern of shadows cast by the sun by the earth's rotation.
Use technology to seek feedback that informs and improves their practice and to demonstrate their learning in a variety of ways.
Students will use the 3Doodler to visually demonstrate how shadows cast by the sun can be used to tell time.
Exhibit a tolerance for ambiguity, perseverance and the capacity to work with open-ended problems.
Students will demonstrate willingness and competency within an open-ended task with more than one possible outcome.
Create original works or responsibly repurpose or remix digital resources into new creations.
Students will use a 3Doodler to innovate a new type of gnomon.
Use collaborative technologies to work with others, including peers, experts or community members, to examine issues and problems from multiple viewpoint
Students will seek feedback from peers before creating a new species of reptile with a 3Doodler.
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