Critical thinking skills figure prominently among the goals for education proposed by educational researchers, parents, and employers. This digest discusses the skills related to critical thinking and three specific strategies for teaching these skills. The first, Building Categories, is an inductive reasoning tool that helps students categorize information by discovering the rules rather than merely memorizing them. Active learning of this sort typically results in better understanding and retention than is possible with more directive teaching. The Finding Problems strategy is a way of framing tasks so that students use skills similar to those needed for the ill-defined problems they will encounter in life. The Enhancing the Environment strategy acknowledges that critical thinking in the classroom is facilitated by a physical and intellectual environment that encourages a spirit of discovery. Seating arrangements and visual aids are useful in promoting active learning. (Contains 6 references.) (SLD)