Sky 1: Objects in the Sky


Purpose
To observe and describe what the sky looks like at different times; to identify objects in the sky and recognize changes over time; to look for objects that are common to the daytime and nighttime sky.

Context
This lesson is part of a four-lesson series in which students observe the daytime and nighttime sky regularly to identify sequences of changes and to look for patterns in these changes. At the K-2 level, learning about objects in the sky should be entirely observational and qualitative. The priority is to get students noticing and describing what objects in the sky look like at different times. (Benchmarks for Science Literacy, p. 62.)
The sun, moon, stars, clouds, birds, and airplanes all have properties, locations, and movements that can be observed and described. Ideally, students should engage in direct observation of both the daytime and nighttime sky throughout this lesson series. However, the recommended Internet resources can be helpful to enhance student experiences, or if opportunities for direct observation are limited. This investigation requires that observations be ongoing, so that students can look for patterns over time. As children become more familiar with objects in the sky, they can be guided to observe changes, such as night and day and the seasons.
In this first lesson, students will investigate objects in the daytime and nighttime sky. This investigation should be confined to observations, descriptions, and finding patterns. Attempting to extend this understanding into explanations using models will be limited by the inability of young children to understand that earth is approximately spherical. Children at this age also have little understanding of gravity and usually have misconceptions about the properties of light that allow us to see objects such as the moon. (Benchmarks for Science Literacy, p. 336.) Thus, these topics should be avoided.
In Sky 2: Shadows, students explore making shadows and tracking the movement of an object over the course of a day.
In Sky 3: Modeling Shadows, students construct models to demonstrate their understanding of shadows.
Sky 4: The Moon has students drawing the moon's shape for each evening on a calendar and then determining the pattern in the shapes over several weeks.
Ideas in these lessons are also related to concepts found in the following benchmark:

  • 11C Common Themes: Constancy and Change (K-2) #1


Planning Ahead
This lesson involves the observation of daytime and nighttime sky. It is important to remind students of the danger of looking directly at the sun.
Materials:

  • Daytime Sky student sheet
  • Nighttime Sky student sheet
  • What Objects Do You See in the Sky?assessment sheet


Motivation
Do a brainstorming activity with students using a prompt like: "Words that come to mind when I think of the sky." You can choose to have students write these words individually, or you can record the group's thoughts at the front of the room, or students can simply call out the words with no recording.

Development
Have students go outside to observe the daytime sky, reminding them of the danger of looking directly at the sun. You can take advantage of the opportunity to discuss the importance of detailed observations, and continue to encourage these once back inside.
Ask students:

  • What objects do you see?
  • Are any of these objects moving? Describe how they are moving.
  • Which of these objects do you think you would be able to see at night?

Have students create a journal page, documenting their observations in words and pictures. The Science NetLinks student sheet Daytime Sky is available for this purpose. Allow students ample time to share their illustrations, or bind them into a class book to read aloud and leave in the classroom library. Lead students in a discussion of how they think the sky's objects will change over time.
Ask students:

  • What do you think will still be in the sky tonight?
  • What do you think will still be in the sky tomorrow?

Have students complete a follow-up activity at home, this time documenting objects in the evening or nighttime sky. Again, have students complete a journal entry based on their observations. You may wish to have students use the Science NetLinks student sheet Nighttime Sky. Allow students ample time to discuss their findings, noting differences due to times at which they observed the sky. Discuss which objects were seen in both the daytime and nighttime sky. This could be repeated for several days, encouraging students to realize constancy and change. For example, take the students outside at different times, in different conditions, etc. Have students draw pictures of objects overhead relative to objects on the ground.

Assessment
In order to summarize Objects in the Sky, as well as make the distinction between daytime and nighttime objects, have students complete the Science NetLinks assessment sheet What Objects Do You See in the Sky? Here, students are asked to draw, and if appropriate label, objects that might be seen in the daytime or nighttime sky. Also, students can revisit the list generated in the Motivation exercise and modify the words that come to mind when they think of the sky. They can include the names of various objects in the sky, as well as some descriptive characteristics.

Extensions
Follow this lesson with the other lessons in the Sky series:

  • Sky 2: Shadows
  • Sky 3: Modeling Shadows
  • Sky 4: The Moon

Sky 2: Shadows


Purpose
To investigate shadows, using literature-based discussion as well as experiences with manipulating shadows.

Context
This lesson is part of a four-lesson series in which students observe the daytime and nighttime sky regularly to identify sequences of changes and to look for patterns in these changes. At the K-2 level, learning about objects in the sky should be entirely observational and qualitative. The priority is to get students noticing and describing what objects in the sky look like at different times. (Benchmarks for Science Literacy, p. 62.)
The sun, moon, stars, clouds, birds, and airplanes all have properties, locations, and movements that can be observed and described. Ideally, students should engage in direct observation of both the daytime and nighttime sky throughout this lesson series. However, the recommended Internet resources can be helpful to enhance student experiences, or if opportunities for direct observation are limited. This investigation requires that observations be ongoing, so that students can look for patterns over time. As children become more familiar with objects in the sky, they can be guided to observe changes, such as nigh and day and the seasons.
In Sky 1: Objects in the Sky, students investigated objects in the daytime and nighttime sky.
In this lesson, students will explore making shadows and tracking the movement of an object over the course of a day to look for patterns. It is best to couple this shadow activity with reading the book, Bear Shadow, and making a map of Bear's neighborhood when the sun is relatively high in the sky, either near the beginning or the end of the school year. You'll want to measure sun shadows at least twice and perhaps three or four times during the year to see how they vary with the time of year.
In Sky 3: Modeling Shadows, students construct models to demonstrate their understanding of shadows.
Sky 4: The Moon has students drawing the moon's shape for each evening on a calendar and then determining the pattern in the shapes over several weeks.
Ideas in this lesson are also related to concepts found in the following benchmark:

  • 4A The Physical Setting: the Universe (K-2) #2


Planning Ahead
Materials for Making Shadows:

  • large pieces of chalk paper
  • soap bubble solution
  • bubble blowers
  • pencils
  • markers
  • paints
  • various objects such as hoops, lace, balls, etc.

Materials for Tracking Shadows:

  • yardstick
  • large coffee can of soil or stones
  • large, flat sheet of cardboard, posterboard, or other heavy paper (at least 2' x 3')
  • marker
  • compass


Motivation
Either individually or as a participatory exercise, you and the students should read Bear Shadow by Frank Asch and discuss. In this story, a bear attempts to escape a shadow that seems to be chasing him. If this will be the introduction to a study of shadows, with particular emphasis on those caused by the sun, spend time finding out what students already know about shadows. You might guide this discussion by asking questions such as:

  • What do you know about shadows that makes the book funny?
  • Why did Bear's shadow disappear when he hid behind a tree?
  • Why did the shadow disappear when he buried it?
  • What makes a sun shadow fall one direction at one time and another direction earlier or later in the day?
  • What other questions do you have about shadows?

Use the responses to help the children shape activities through which they will discover the answers to their questions.

If you have already begun the study of shadows and have measured sun shadows at least once, your discussion of Bear Shadow can be more pointed. In addition to the kinds of questions above, you can, for example, discuss the time of day when the various events occur and the direction Bear's shadow will fall at these times.

Development
Investigating Shadows
Eyes on the Sky, Feet on the Ground: Hands on Astronomy Activities for Kids, offers various astronomy topics and activities. Under The Earth's Rotation, read Activity 1-1: Making Shadows, and complete the suggested activities with students. Here, students use different objects and angles to create, trace, and manipulate shadows. This activity includes a thorough list of discussion questions, as well as ideas for extending a study of shadows. In addition to the questions included in the lesson, ask students:

  • How can you "make" a shadow?
  • What is the light source?
  • How is the shadow similar to the object you used to make it? How is it different?
  • How can you change the size of your shadow?
  • How can you change the shape of your shadow?
  • How can you change the position of your shadow?

In Activity 1-2: Tracking Sun Shadows, also found on The Earth's Rotation page, students use a yardstick and coffee can full of stones to create a shadowstick. Students visit the shadowstick throughout the day, taking periodic measurements by tracing the line of the shadow and marking the time of day. Encourage students to begin making predictions about where the shadow might fall next. This activity can also be conducted as an indoor activity for small groups, using a drinking straw and clay. Full instructions and list of materials for both activities can be found at the site.
Follow the activities given at the site, but instead of just marking a point at the end of each shadow, draw the full line from the center of the posterboard to the end of the shadow. (These lines will be helpful when students are later asked to measure the shadows.) Each time students visit the shadowstick in the course of the day, ask them to compare the new shadow line to those drawn previously: Has it changed? How has it changed?
At the end of the day, bring the posterboard inside. Have student volunteers measure the distance from the center of the board (where the lines cross) to the end of each shadow line using cubes. Use the cubes to create a bar graph that represents the length of the shadows at the various times observed.
Ask students:

  • What does the graph look like?
  • When is the shadow shortest?
  • When is it longest?
  • What do you notice about the lines? Does the pattern of the lines remind you of anything?


Assessment
Reread Bear Shadow. As a class, identify those aspects of the story that are purely fictional and those that “could happen,” paying particular attention to how shadows change during the day. Compare the shadows in Bear Shadow to those students made and tracked in the Development activities. You could revisit the discussion questions listed in the Motivation, especially focusing on the last one, "What other questions do you have about shadows?" You could spend time answering the students' questions, as well as generating ones to be answered in the other lessons of this series.

As a class, create a nonfiction version of the story.

Extensions
Follow this lesson with the next lessons in the Sky series:

  • Sky 3: Modeling Shadows
  • Sky 4: The Moon

Sky 3: Modeling Shadows


Purpose
To demonstrate understanding of shadows by creating a physical model of concepts learned.

Context

This lesson is part of a four-lesson series in which students observe the daytime and nighttime sky regularly to identify sequences of changes and to look for patterns in these changes. At the K-2 level, learning about objects in the sky should be entirely observational and qualitative. The priority is to get students noticing and describing what objects in the sky look like at different times. (Benchmarks for Science Literacy, p. 62.)
The sun, moon, stars, clouds, birds, and airplanes all have properties, locations, and movements that can be observed and described. Ideally, students should engage in direct observation of both the daytime and nighttime sky throughout this lesson series. However, the recommended Internet resources can be helpful to enhance student experiences, or if opportunities for direct observation are limited. This investigation requires that observations be ongoing, so that students can look for patterns over time. As children become more familiar with objects in the sky, they can be guided to observe changes, such as nigh and day and the seasons.
In Sky 1: Objects in the Sky, students investigated objects in the daytime and nighttime sky.
In Sky 2: Shadows, students explored making shadows and tracking the movement of an object over the course of a day to look for patterns.
In this lesson, students will construct models to demonstrate their understanding of shadows. Many questions and suggestions for variants on the activities are presented to allow you to tailor this lesson to your particular needs. It is best to make the map of Bear's neighborhood when the sun is relatively high in the sky, either near the beginning or the end of the school year. You'll want to measure the sun shadows with students at least twice, and perhaps three or four times during the year, to see how they vary with the time of year.
Sky 4: The Moon has students drawing the moon's shape for each evening on a calendar and then determining the pattern in the shapes over several weeks.
Ideas in this lesson are also related to concepts found in the following benchmark:

  • 4A 11C Common Themes: Constancy and Change (K-2) #1


Planning Ahead

Review the activity used in the Development section to determine which type of model your students will construct. Gather the required materials, and prepare to do the activity in the conditions described.
Materials:

  • Bear Shadow by Frank Asch

Select one (or more) of the following models:

  1. One-dimensional map/model:
  2. a large sheet of paper or poster board
  3. pencils, crayons, and markers
  4. Three dimensional map/model:
  5. some appropriate area in the classroom
  6. cardboard
  7. scissors
  8. glue
  9. tape
  10. pencils, crayons, and markers
  11. a bright lamp
  12. Outdoor three-dimensional map/model:
  13. an appropriate place on the school grounds
  14. larger pieces of cardboard
  15. scissors
  16. glue
  17. tape
  18. pencils, crayons, and markers
  19. any additional material students can use to create landmarks like the tree, Bear's house, and so on


Motivation

If you wish, reread Bear Shadow by Frank Asch and discuss.
You should have completed Shadows, the second Science NetLinks lesson in this series, or have measured sun shadows in some other context, so your discussion can be more pointed. You can, for example, discuss the time of day when the various events occur, and the direction in which the Bear's shadow will fall at these times.


Development

Divide students into groups of 3-4. Each group will make a 3-D model of the neighborhood where Bear lives. The map/model should show clearly which direction is north, either with an arrow on a map or by orienting a three-dimensional model correctly with respect to the actual directions. Be sure the map/model includes:

  • Bear's house
  • the pond where he went fishing
  • the brook he jumped over
  • the tree he hid behind
  • the cliff he climbed
  • the place where he tried to nail the shadow to the ground
  • the place where he dug the hole to bury the shadow

One-dimensional map/model:
The simplest way for children to construct their maps/models is to draw them on paper, but this is also the most abstract and demands a great deal of transfer from the observational world of shadows cast by real objects on real surfaces to imagining an object drawn on paper casting a shadow. This approach should be used with older children who have had some previous experience drawing maps of such places as their homes, their school, or a small neighborhood. The added difficulty of mapping an imaginary neighborhood, where the only clues to the relative positions of things are the shadows that they cast or are cast upon them, is substantial.