Modeling Sunlight Angles

4.A Develop, revise, and use models of the Earth-Sun system to create mathematical relationships of the seasonal patterns of the position of the Sun in the sky and of temperatures over the surface of Earth.

If students do not make the connection that sunlight heats up Earth’s surface, prompt them to think about differences in how they feel standing in sunlight versus the shade to call back to their prior knowledge. If students do not connect light energy per square on graph paper’s relationship to intensity of light, ask them to share their noticings about the apparent brightness of the light on the graph paper.

It is common for students to combine their ideas about proximity and warmth with the new ideas about the tilt of Earth to form a hybrid conceptual model for the system where proximity is still the primary cause of temperature patterns. If students were very convinced that distance from the Earth to the Sun was a factor in causing seasonal temperature change, take the time here to make a connection back to Seasonal Temperature Data to remind students that the data does not support that explanation, but the results from this investigation explain seasonal temperature change better. Have students take a moment to re-examine the distance data provided in the handout to understand that during the winter, the part of Earth where we live is closer to the Sun in its orbit.

If students are struggling with the connection between energy and temperature, remind them of what we figured out in OpenSciEd Unit 6.2: How can containers keep stuff from warming up or cooling down? (Cup Design Unit): that more energy transferred to Earth’s surface translates to more movement of the particles, which means higher temperatures.

Discuss initial ideas about how we explain seasons. Present slide I and tell students to turn and talk with a partner about the prompt on the slide: How do we know when one season ends and another begins?

Look for students to mention the calendar dates we’ve used in class, changes in weather, or changes in the amount of daylight. Handout Defining Seasons or provide students with the link to https://www.ncei.noaa.gov/news/meteorological-versus-astronomical-seasons and say, I have a reading that might help us figure out how scientists determine when one season ends and another season begins. Read this tonight and come back next time ready to tell us what you think - which of these ways of marking seasons is most relevant to you? Why? It would be really great to talk with someone else about seasons, too - tell them what you’ve figured out in class and ask them what they think about the information you find in this article.

HOME LEARNING OPPORTUNITY

• Note that the information in this article is supplemental and if students do not have a chance to read it, it will not hinder their understanding of the ideas in this unit. Home learning work should not be scored.
• Encourage students to share this article with someone else - a friend, a trusted adult, or even a younger sibling. Ask students to read the article, possibly with that other person, and then talk about how they think about seasons and connections they might have with seasonal changes, equinoxes, and/or solstices.
• If time allows, you might choose to have your students read this article with a partner during class instead of taking it home.