With funding and support from the NASA Office of Space Science through the IDEAS program, a team of teachers from Gullett Elementary School in Austin, Texas, and a research scientist at the University of Texas, worked on activities and curriculum to capture students’ natural excitement about outer space. In order to include a strong daytime component to the program, the motion of the sun across the sky was an obvious choice. This article describes how a Sun Tower was used as a tool to engage students in scientific inquiry and reinforce their understanding of the dynamic universe.