This zip file contains many different activities (57 pages of student handouts and 2 PowerPoints with a total of 126 slides) which can be used to compose a unit introducing the earth's changing environment. Concepts addressed include observations, inferences, percent deviation (error), finding volume, density, rates of change, cyclic changes, dynamic equilibrium and many others. The learning objectives and specific contents of this set of materials is listed below. This set of activities is s