This document contains plans for 31 lessons intended to develop thinking skills using library media center materials primarily in the areas of language arts and social studies. Designed for various grade levels in the K-12 range, each of the lessons contains the following components: (1) behavioral and thinking skills objectives; (2) desired disposition and/or attitudes regarding the lesson experience; (3) lesson plan core, including the immediate purpose of the lesson, student background knowledge, student activities, instructional materials, instructional techniques, lesson sequence, and metacognition; and (4) transfer, including descriptions of additional applications of the thinking skills and follow-up activities. The appendix includes a grade use chart for the lesson plans, a list of 10 software packages which promote thinking skills, descriptions of 7 software packages for critical thinking practice, and a 40-item annotated bibliography. (MES)