ESL classes are taught by individuals who possess a teaching license and either a Bachelor's or Master's Degree, if the classes are through public schools. Specific requirements vary among U.S. states.
In addition to educational credentials, ESL teachers must possess knowledge of instructional methods for K-12 grades. They must also be familiar with different cultures, in order to determine the best approach based upon the students' country of origin. Additionally, creativity and adaptability allow the teacher to adjust lessons to meet the unique needs of every student.
Continuing education is common for ESL instructors, including completion of coursework for advanced degrees.