If you want to teach in high school level, then you will require a minimum of a bachelor's degree. High school teachers should have a bachelor's degree and the licensing required by their state prior to their teaching. Licensing requirements usually vary by state.
It depends on what level you want to teach at. At the high school level, you'd need to take the classes required for a Bachelor's in education, and some extra classes in psychology. At the community college level, you'd at least need a Master's. At the university level, you'd need a Ph.D.