Active Calculus: Single Variable (2nd Ed) is an open-source textbook that is available free in HTML and PDF, as well as in this low-cost print version. The style of the text requires students to be active learners: there are very few worked examples in the text, with instead 3-4 activities per section that engage students in connecting ideas, solving problems, and developing understanding of fundamental calculus ideas. Each section begins with a brief introduction and a preview activity designed to be completed before class; each section concludes (in HTML) with live anonymous WeBWorK exercises for immediate feedback, followed by a few challenging non-WeBWorK exercises. The text is suitable for a 2-semester course in single variable calculus, and there's a Spanish translation of the 1st edition. The author maintains a large repository of available-upon-request ancillary materials including sample syllabi and course calendars, additional WeBWorK exercises, supplementary written homework exercises, laboratory activities, weekly quizzes, and final exams. There is also a large instructor user community that is connected through an online Google group. Learn more at activecalculus.org.
