This course combines aspects of quantitative reasoning and mathematical modeling. Quantitative reasoning is the ability to make sense of the numbers that surround us: to find patterns, to estimate, and to create mathematical models that help us make informed decisions. In this course, students learn to use difference equations to describe complex natural phenomena. Using spreadsheets as computational and graphical aids they develop the basic algebraic, computational, graphical, and statistical skills necessary to understand these models, and learn why difference equations are the primary tools in the emerging theories of chaos and complexity. This is a required course for the Interdisciplinary Science Major and is taught in Fall & Spring.