Grade Levels: K-3

This page provides information to support educators and families in teaching K-3 students about the sun. It is designed to complement the Sun topic page on BrainPOP Jr.

The Sun is the center of our Solar System and the planets, moons, and other bodies in our Solar System orbit, or go around, the Sun. The Sun is a star, which is a body of hot gases that makes its own light and heat. This movie will describe the Sun and how it affects our planet. We highly recommend reviewing the Earth movie before beginning this topic. The Sun plays an important role in many food chains, powers the water cycle, and affects changes in weather. You may wish to review the Food Chain movie and explore the Water Cycle to reinforce information that is summarized in this movie. The Seasons movie also provides a review of basic concepts.

Your children should understand that the Sun is a star and not a planet. According to the International Astronomical Union, a planet is a body that orbits a star. It is massive enough to be rounded by its own gravity, but not massive enough to cause thermonuclear fusions. The Sun is capable of thermonuclear fusion, and it is so enormous that it accounts for over 98% of the entire Solar System’s mass. The Sun is about a million times bigger than Earth by volume, and over one hundred Earths could fit across the middle of the Sun. Even though the Sun is over 93 million miles away, it’s Earth’s closest star. It appears largest in the sky because it is closer than other stars in our galaxy.

Help your children understand that the Sun is made of gases; primarily hydrogen and helium. Some children may make the connection that some balloons are filled with helium. In the Sun’s core, hydrogen is converted to helium through nuclear fusion. As a result, an enormous amount of energy is released. The outer layer of the Sun, called the photosphere, is about 9,900 degrees Fahrenheit, which is about 5,500 degrees Celsius. The core, or center, is significantly hotter with temperatures reaching to 27 million degrees Fahrenheit or about 15 million degrees Celsius. Temperatures this high might be hard for many children (and adults) to comprehend. We recommend putting these measurements in context. For example, a typical oven only goes to 500 degrees Fahrenheit and water boils at a mere 212 degrees Fahrenheit. What was the hottest day of the year? What is the temperature of the hottest place on Earth? Help your children understand the Sun’s energy.

Almost everything on Earth depends on the Sun’s energy in some way. Have your children think about how they rely on the Sun. What did they eat for lunch or dinner? How did their vegetables grow? What did the grass and grain used to feed livestock need to grow? The Sun plays an important role in most food chains. Together, come up with a food chain that relies on the Sun. For example, a plant uses the Sun’s energy to grow. An insect might eat the plant, and a mouse might eat the insect. A snake might eat the mouse, and an owl might eat the snake. Thus, the animal at the top of the food chain relies on the Sun in order to survive.

The Sun also plays an important role in the water cycle. The water cycle shows how water moves through, on, and under Earth’s surface. The Sun warms water in our lakes, streams, and oceans. Water evaporates and goes into the atmosphere. As it cools, water droplets come together to form clouds. When the clouds can no longer hold water, precipitation, such as rain, snow, sleet, or hail, might fall. Water then returns to our lakes, streams, and oceans to be warmed by the Sun and the cycle begins again.

The Sun also plays a crucial role in weather changes. Remind your children that Earth is tilted at an angle. As Earth orbits the Sun, the Sun shines light on Earth at different angles. While one part of Earth is tilted toward the Sun, another part is tilted away from the Sun. The angle at which the Sun hits Earth causes different parts of Earth to experience different seasons.

Your children should understand that people have been studying and tracking the Sun for thousands of years. Stonehenge is a monument in England that scientists believe was erected sometime between 2500 and 2200 BC. Different parts of the monument line up with the summer and winter solstice, and the spring and autumn equinox. Over two thousand years ago, ancient Chinese studied the Sun and kept careful records of their observations. They were the first to record sunspots, which are cooler, darker areas in the Sun’s outer layer. Ancient people who lived in the area that is now Mexico built pyramids to honor and track the Sun, and Aztecs created calendars based on their observations of the Sun’s path. People have been using sundials for hundreds of years. Today scientists use powerful tools to study Earth’s closest star. The European Space Agency and NASA launched the Solar and Heliosphere Observatory (SOHO) in 1995. The goal is to study the internal structure of the Sun and gather information about solar phenomena.

Remind your children that they should never look directly at the Sun. The harmful rays can damage eyes. Instead students can research images on the Internet or at their local library. They can visit a local science museum or observatory to learn more. They can also create their own pinhole camera by poking a small hole in a piece of paper and holding it up to the light. This will cast an image of the Sun on to another piece of paper.

Earth is just a small part of our vast Solar System and even a smaller part of the Milky Way. Encourage your children to ask questions about the world around them and beyond. Challenge them to make predictions and research to find the answers to their questions.