In this video segment from Teaching Earth and Space Science, teacher Mark Goldner works with his students on a lesson about the scale of the solar system. He begins the inquiry-based lesson by discussing planetary distances and sizes with the students. He finds that teaching astronomy is challenging because the subject is so abstract. To compensate, he creates a “solar-system experience” for his class in which the students model planetary distance in an outdoor walking activity. This exercise stimulates students’ investigations into astronomy and helps them understand difficult concepts through real-world modeling. In addition, he encourages the students to challenge their thinking by working with data to answer questions.