This unit provides students with the tools to analyze the first order forces that influence Earth's weather and is subdivided into three major sections. Each section will take a little more than one week to complete. 1.Basic structure of the atmosphere and the factors that shape it. Foremost is the particle nature of the gases that make up the atmosphere, and the forces that act upon the gases. Also included is the role of water and its changes of state in the energy economy of the atmosphere. 2.The circulation of air parcels as they absorb and release energy from the sun. This fundamental motion is simple, but can be used to explain complex phenomena like warm and cold fronts. 3.The effect of the spinning of Earth upon the motion of circulating air masses. The winds that we experience are shaped more by the Coriolis effect than by thermal effects. This counter-intuitive idea is one of the more difficult ideas for a child to learn. At the end of the formal exercises, students are invited to undertake a five day research project on a weather event of interest to them.