In the United States, individual states dictate who can and cannot become a teacher. However, in all states, in order to teach in a public school, you have to complete at least a bachelor’s degree in education, which takes about four years. A bachelor’s degree will prepare you through classroom education, as well as give you the opportunity for hands-on learning as a student teacher, where you’ll actually get in the class room with real students. As part of your bachelor’s degree, you might also minor in a specific subject like history or math, which allows you to be better prepared for teaching at the secondary level.
http://onlinedegreesineducation.org/becoming-a-teacher-how-much-education-do-you-really-need/
http://onlinedegreesineducation.org/becoming-a-teacher-how-much-education-do-you-really-need/