As a teacher, you have to follow the curriculum, programs and the textbook series the corporation adopts. Most public corporations have adoptions of materials on a rotating basis. The year span between adoption depends on the state and money distribution. The number of years between subject areas can also vary widely. Corporations spend a large amount of money on these materials and the expectation is to follow them. As a coach, I agree with this ideal…mostly.
There is never one program that is a cure-all for your students. A teacher must constantly differentiate based on student needs. Teaching is an art where nuance is required. A knowledge base of your content is important but a teacher also has to synthesize info so others can learn it. Many factors play into a strong teaching strategy and most can be learned. Our natural tendencies can make certain aspects easier. There are fundamental skills such as conveying a proper objective, motivation techniques, the ability to give academic feedback and how to structure and pace a lesson. Methods for teaching problem solving and thinking is imperative as well. To accomplish these skills you must know how to develop relationships with your students.
The nuance enters when you must decide what you believe as a teacher. You have to have a philosophy you can use as a measuring stick to what you are willing to accommodate for and what you want to fight back on.