There appears to be a lo0t of differences for what is required:
In the United States, there is no central ministry that approves teacher education programmes; each state sets its own standards for programme approval and teacher licensing, which leads to a wide variation in the quality of teacher preparation programmes. However, while programmes differ from state to state and school to school, all emphasize three areas to different degrees: the liberal arts, with a focus in a specialty area; pedagogy, the study of how to teach; and field experience, or practice teaching in a classroom.
http://www.internationalgraduate.net/teaching.htm