'A series of workbooks, SPIRAL Physics, have been developed and used in place of a standard textbook in the introductory physics course for undergraduates. The workbooks, designed for use in an active learning environment, arrange topics such that students receive repeated exposure to concepts over an extended time interval, each time with an incremental increase in complexity. These workbooks emphasize multiple representation problem solving techniques and goal-less problem statements. The course is divided into Calculus-based Introductory Physics and Algebra-based Introductory Physics. Each module can be downloaded as a PDF file.'