A teacher must understand the central concepts, tools of inquiry, and structures of the disciplines taught and be able to create learning experiences that make these aspects of subject matter meaningful for students.
When teaching one of the most important things to do is to create a purpose for all lessons and activities. A good lesson is meaningful inside and outside of the classroom. A good lesson is relevant to the topic. It is well researched and accurate. It allows students to have a clear understanding of the topic. It is developmentally appropriate.