This paper presents the process of simulation modeling of Earth-to-Air Heat Exchanger (EAHE) systems (earth tube system) as part of a whole building simulation using the EnergyPlus program for the performance analysis of a school building in the Mid-atlantic region. The earth tubes buried under the ground can provide major benefits in terms of energy and demand savings. The installation depth of the earth tubes was calculated and optimized based on the local soil physical conditions using the MATLAB program. Parametric analysis includes pipe length, radius and air velocity inside the pipes. The overall performance and energy savings are presented.