Which visa will I need in order to become a legal teacher?
A non-immigrant 'B' visa is generally the visa you need to obtain if you are looking to work here as a teacher.
If you are applying for a non-immigrant 'B' visa, it's a good idea to call your nearest embassy or consulate ahead of time and find out exactly what they require if you want to apply for a non-immigrant B, - although this information is usually on their website and updated regularly.