Within the United States, to teach within the public school system you must have a bachelor's degree in a teacher education program and state teacher certification. This would take approximately four years as a full-time student, provided the program is followed as prescribed by the college or university.
http://www.helpforschools.com/sikb/legal/qualifications_teachers.shtml
It will probably take 7 years to become a music teacher.
5 years
about 4 to 6 years
Four Years are needed
4 to 6 years at the most
4
A BS in Education can on average be achieved in four years.
3 or 4 depending on what course you do
8 or up
2 years
Most states require you to have at least an Associates degree before you can become a preschool teacher. Sometimes you can start as an assistant teacher and learn under the tutelage of a lead teacher.