Tree Shadows (Phenomenon)

Contributor
Ian Gates
Type Category
Instructional Materials
Types
Animation/Movie , Phenomenon
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

When watching this video, students will observe tree shadows changing direction while the sun appears to move in the sky over the course of the day. This anchor phenomenon can be used to prompt student questions and initiate further investigation into its cause.

Intended Audience

Educator and learner
Educational Level
  • Grade 5
  • Informal Education
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

5-ESS1-2 Represent data in graphical displays to reveal patterns of daily changes in length and direction of shadows, day and night, and the seasonal appearance of some stars in the night sky.

Clarification Statement: Examples of patterns could include the position and motion of Earth with respect to the sun and selected stars that are visible only in particular months.

Assessment Boundary: Assessment does not include causes of seasons.

This resource was not designed to build towards this performance expectation, but can be used to build towards it using the suggestions provided below.

Comments about Including the Performance Expectation
Students could develop an investigation to answer questions that they develop after viewing the video. An investigation might include collecting shadow data at regular intervals during the day. The length of the shadows or the angle of shadow direction can be represented in data tables and graphs. Using a protractor, students can also measure the altitude of the sun at the same regular intervals daily and represent the data in tables and graphs. A comparison of these data sets will show a cause and effect relationship. See related NSTA-curated resource: Suntracks I (http://ngss.nsta.org/Resource.aspx?ResourceID=799).

Science and Engineering Practices

This resource was not designed to build towards this science and engineering practice, but can be used to build towards it using the suggestions provided below.

Comments about Including the Science and Engineering Practice
Students will notice that the sun appears to move in the video from the left side to the right side, while the tree shadows move from right to left. The video does not show the cardinal directions so students would not be able to determine direction of travel without further investigation. After viewing the video, students can be guided to develop questions to drive an investigation. “How do shadows change daily?” “Is there a pattern to shadow movement?” “What causes the shadows to change?” These could be charted for the class by the teacher. Students could then plan and conduct investigations to answer these questions.

Disciplinary Core Ideas

This resource was not designed to build towards this disciplinary core idea, but can be used to build towards it using the suggestions provided below.

Comments about Including the Disciplinary Core Idea
To accurately explain this phenomenon, students will need to develop an understanding that the rotation of Earth causes the apparent movement of the sun from east to west in the daytime sky. This also causes the daily pattern of change in altitude of the sun. The position and apparent movement of the sun causes the daily changes in the length and direction of shadows creating a cause and effect chain. After watching the video and collecting/analyzing their own data, students can use three-dimensional models of the Earth and sun to attempt to explain their observations. Students should be given multiple opportunities to share their thinking with each other as they make sense of this phenomenon.

Crosscutting Concepts

This resource was not designed to build towards this crosscutting concept, but can be used to build towards it using the suggestions provided below.

Comments about Including the Crosscutting Concept
To explore this phenomenon, students can conduct investigations and observe the daily patterns in the sun’s position in the sky and the length and direction of shadows. If it is difficult to directly observe the daily pattern of position of the sun in the sky, planetarium software such as Stellarium could be used. See related NSTA-curated resource: http://ngss.nsta.org/Resource.aspx?ResourceID=84

Resource Quality

  • Alignment to the Dimensions of the NGSS: - none -

  • Instructional Supports: - none -

  • Monitoring Student Progress: - none -

  • Quality of Technological Interactivity: - none -