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National Science Teachers Association
Discovering Science: Lessons Plans and Experiments for the Classroom
Topic: Sun and Shadows
Grades: 4-5
Allocated Time: Two sessions/20-35 minutes Student Population: __students/_boy_ girls
Standards
Next Generation Science Standards: 4. Energy, PS3-2. 5. Earth’s Place in the Universe, ESS1-1, ESS1-2,
ESS1.B. 3-4. Engineering Design, ETSI-1
Common Core State Standards: English Language Arts, Writing, Text Types and Purposes, W.4.3, W.5.3
Common Core State Standards: Math, Measurement and Data, 4.MD.B.4, 5.MD.B.2
Goals for Understanding
Students will learn about the Sun’s light and how shadows are created.
Objectives
Students will
 create a simple sun dial and understand how it marks time.
 investigate patterns of light and shadows.
 write paragraphs describing their shadows.
Materials Needed (See science activity attached for additional materials.)
 sidewalk or blacktop in sunny spot
 chalk
 200 watt light bulb
 projection screen or light colored wall
 various objects to create shadows
Anticipatory Set
Ask students what time it is. Ask: At what time do we go to lunch? to gym class? Why do people
need to know the time of day or night? What did people use hundreds of years ago to tell time? How
did ancient peoples tell the time? (Sun, shadows, etc.) Why might they have needed to know the time
of day long ago? What role did the Sun play in telling the time of day?
Instruction (I/Teacher’s role)
Review key content words (sun, light, shadow, etc.).
 Explain that long ago, people used the position of the Sun in the sky to tell time.
They did this by using sundials.
 Light travels faster than anything in the universe. It takes about eight minutes for the Sun’s
light to reach Earth. Sunlight travels in a straight line from Sun to the Earth.
 Sunlight keeps moving. If a solid object gets in the way, light will go around the object,
creating a shadow. A shadow is an area that light does not hit.
 The farther from the sunlight an object is, the larger the shadow. The closer to the sunlight an
object is, the smaller the shadow.
 Shadows look different in winter and summer. Shadows also look different in the morning
and afternoon. This is because of the Sun’s position in the sky as Earth moves around it.
 The Sun is highest in the sky at noon, causing a shorter shadow. The Sun is lower in the sky
in the afternoon, causing a longer shadow.
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Guided Practice (We/Students with Teacher’s guidance)
Assign groups of students to work together. In a sunny spot ask students to hold one hand above a
sidewalk or blacktop. Ask: Do you see shadows? Let students move their hands to see the shadows
move. Ask students to predict how they can make their shadows grow bigger or smaller. Students can
then move closer or farther away. Were the predictions correct? Let students take turns outlining their
shadows with chalk and to decorate the outlines as they stand in different positions.
Review and Summary
Create a shadow word web, which could be used to facilitate writing about shadows. On an easel
pad, write the word shadow in a circle. Extend six to eight lines from the circle. Ask: What words
describe about shadows. Record the words on the lines. (darkness, shapes, gray, trace, dim, etc.)
Independent Learning (You/Student)
Ask students to write paragraphs about their shadows. They should include a main idea and details
about shadows, and reflect on their experiences about light, shapes, sizes, etc. while making shadows
outdoors. Remind students to use the shadow web words.
Checking for Understanding (Assessing)
Review students’ paragraphs for accuracy and creativity.
Cross Curriculum Extension: Math/Science
Let students analyze the size of a shadow as it relates to the distance of an object from a light source,
using a 200-watt light bulb. On an easel pad, students should create a four-column table. They should
set the object a fixed distance from the light to a screen or white wall. They should record the
following in each column. Column 1: the distance in the first column of the table. Column 2: record
the measurements as they change the distance of the object from the light several times, moving it
farther away each time. Column 3: the height of each object used should be the same. Column 4: the
height of the shadow formed each time they moved the object farther away from the light. Ask: What
happened each time you moved the object farther away? What pattern do you see in shadow size?
Adaptation (Gifted and Talented or English Language Learners)
Ask students to explore the many aspects of the Sun—its energy, power, heat, light, and danger.
Encourage students to write cinquain poems about the Sun. Cinquain poems are five-line poems
meant to convey emotion or mood. The form of a cinquain is often: first line: one word (title),
second line: two describing words; third line: three action words, fourth line: four words that show
feeling about the subject; fifth line: one word that is a synonym for the title word.
Additional Reading
 Shadow, by Suzy Lee
 Solar Energy: Running on Sunshine, by Amy Hansen
 Sunlight, by Erin Edison
 Super Shadows, by Nadia Higgins
Additional Resources
 National Science Teachers Association
Science and Children, “Talking about Shadows,” October 2012, pages 32-34.
learningcenter.nsta.org/product_detail.aspx?id=10.2505/4/sc12_050_02_32S
 See examples of formats of cinquain poems at
http://hrsbstaff.ednet.ns.ca/davidc/6c_files/Poem%20pics/cinquaindescrip.htm
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
For the history of telling time, see http://www.time-for-time.com/history.htm
NSTA
Discovering Science
Grades: 4-5
Title: The Sun
Demonstration: How Can You Use the Sun and Shadows to Tell Time?
Standards: Next Generation Science Standards: Earth and Space Sciences, Earth’s Place in the
Universe, ESS1.A, Physical Sciences, Energy PS3.B
What you need
 stick
 sunny, flat outdoors spot
 clock
 10-12 rocks about 3 to 5 inches wide
Time: 10-12 hours
What you do
1. Push the stick into the ground in a sunny place.
2. Check the clock. When it is 7 a.m., place a rock at the end of where the shadow falls.
3. Write 7 a.m. on the rock.
4. Repeat this every hour, on the hour, until 5 p.m.
5. Label each stone with the corresponding hour of day.
6. To tell time, look at the shadow caused by the stick. Which stone is it on? If the shadow
is halfway between two stones it would be half past the hour. How did you do?
Is the time correct?
What you found
You can tell the time by viewing the shadow cast by the Sun as it shines on the stick of a sundial
at different times of the day. In the early morning and late afternoon the Sun is lower on the horizon.
This makes shadows appear longer. At midday, the Sun is almost overhead. This makes shadows
appear shorter. Note: Early civilizations, including the Egyptians, Greeks, and Romans, are credited
with using a stick as a device to tell time. The stick, called a gnomon, (nom-on), is the basic part
of a sundial. It is the part that casts the shadow.
Conclusion
The angle of the Sun on the horizon changes during the day. The Sun’s angle determines the length
of the shadow cast by the sundial’s stick. The shadow enables you to tell the time of day.
Explore More!
Find out how we get day and night. Gather a lamp (the Sun) and an orange (Earth), and go into
a dark room (space). Hold the orange in front of the lamp. You’ll see only half of it is illuminated.
This represents day. The other half of the orange is dark. This represents night. Stick a straight pin
partway into the orange. You are marking a place on Earth. Spin the orange on an imaginary axis
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in front of the Sun. Do you see how the spot you pinned on Earth gets both day and night?
What happens at the imaginary poles? Do they get day and night?
Name _____________________________________________________________________
NSTA
Be a Scientist: Ask, Answer, and
Discover!
Sketch the stick of the sundial and its shadow
in the early morning and indicate the time.
Sketch the stick of the sundial and its shadow
sometime in the afternoon, and indicate the time.
1. People used Sun to help them tell time long ago. How else might people have used the Sun?
________________________________________________________________________
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2. Write one fact about the Sun or shadows. Write one opinion about the Sun or shadows.
Fact:
_________________________________________________________________________
Opinion:
_________________________________________________________________________
3. Drawing conclusions. Based on what you observed and learned in the experiment above, what
can you conclude about why shadows change and why they seem to move?
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___________________________________________________________________________
4. Many ancient cultures used sundials. People eventually determined that noon was when the Sun
was directly overhead and shadows of people and objects were at their shortest. As technology
advanced, people began to use clocks and watches instead of sundials. Yet, many people still
checked the time by using a sundial. Often, clock towers were erected in the center of town to
ensure that everyone used the same time.
Why do you think people continued to check sundials to verify the time?
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