PowerPoint slides will be used to reinforce the concept that revolution and the earth's tilt result in seasons. The angle of the sun's rays during the seasons and the affect on seasonal climate will be noted. The STARLAB Northern Sky cylinder will then be set to demonstrate the position of the sun on June 21st, September 21st, December 21st, and March 21st (the vernal equinoxes and solstices). The direction of sunrise and sunset, altitude of the noon sun, and the length of the sun's path will be observed by the students.