One of a series of curriculum materials in U.S. history designed to teach critical thinking skills systematically, this teacher's guide presents a series of supplementary ready-to-use lesson plans for teaching high school students about the exploration of early America, the colonies, the revolution, and the Constitution. The introduction presents a rationale for the "history and logic" project (HAL) and points out differences between the HAL approach to critical thinking and the inquiry method. The introduction is followed by a guide to critical thinking which offers an explanation of types of arguments in history, examples of fallacies, a checklist for evaluating evidence, a method of analyzing value positions, ways of identifying assumptions, and models for analyzing arguments. Other methodologies include: problem worksheets; debate topics and transcriptions; and analyses of interpretations, in which students are presented with rival interpretations of historical events, rewritten at a high school vocabulary level. The teacher's guide includes a rationale for the program, detailed lesson plans keyed to student booklets, answer keys, test questions, a chart of critical thinking skills taught in each lesson, and difficulty-level coding. The document concludes with a separate section (the source "envelope") containing an outline of the guide to critical thinking, introductory worksheets, a unit on Salem Witchcraft for advanced students, sources for debate on the Stamp Act, and test questions (LH).