Algebra concepts are introduced on an intuitive level in Book 1. Some of the topics convered in Book 1 are coordinate graphing, integer concepts, and writing and evaluating expressions. Students also use graphs, tables, and equations to show relationships. Throughout Book 1, students work with concrete models as often as possible and whenever appropriate. In Book 2, students explore algebra ideas in most of the modules. Topics include writing and solving linear equations, writing and graphing inequalities, and using formulas. Book 3 builds on the concepts explored in the earlier books. Students continue to write and solve linear equations, but they also explore quadratic and exponential equations.