The document discusses adapting instructional materials. It defines adaptation as modifying materials to suit intended learners. There are several reasons for adapting materials, such as achieving congruence between variables like teaching style and student needs, and making materials more meaningful. Principles of adaptation include increasing relevance, personalizing to learning styles, and localizing content. Guidelines for adapting include choosing credible authors, modifying ideas as needed, and validating adapted materials with experts. The document also provides tips for adapting textbooks and supplementary materials like modifying content, tasks, and expanding materials.