Experiences with scale and relative size help students understand how and why eclipses occur. Because the earth turns daily on an axis that is tilted relative to the plane of the earth's yearly orbit around the sun, sunlight falls more intensely on different parts of the earth during the year. The difference of the heating of the earth's surface produces seasons. Measure the amount of surface covered by the light and speculate on the amount of light hitting the earth when it covers a larger area. The Museum of Science in Boston has an exhibit that shows the length of a person's shadow as the earth orbits the sun.
Students often think that the distance from the earth to the sun determines the seasons.
Help students to relate the tilt of the earth as it orbits the sun to seasons and weather patterns.