Before the exercise, ask students to recall sources of light. Use this worksheet to explain that the brighter the light source, the more space it can light up. Identify the different light sources in the pictures, then check the brighter light source in each pair. The biggest natural source of light is the sun.
Young learners gain understanding when using picture clues when reading. Looking at illustrations can help students learn the meaning of key vocabulary when reading fiction or informational text. Ask your students to look at the worksheet and observe what they can learn from the picture. It's a great comprehension strategy for early readers.