This document discusses the importance and purpose of lesson planning for teachers. It defines a lesson plan as a blueprint or plan of action for teaching a portion of the curriculum within a class period. Good lesson planning is key to successful teaching as it allows teachers to anticipate student reactions, visualize learning situations, and avoid foreseeable difficulties. A lesson plan provides teachers with guidelines for teaching the material, analyzing the content, and evaluating student outcomes based on anticipated goals. The principles of lesson planning emphasize preparing a flexible plan, having mastery of the content, knowing students, ensuring active participation, and varying activities to avoid monotony.