People do learn outside of classrooms.
Museums, zoos, and libraries spend millions on their educational efforts. Businesses educate, and a teaching certificate is generally not a pre-requisite for a job in business. The mass media is the largest and most influential educational platform in the modern world. Educational institutions, businesses and government agencies at home and abroad are looking for people with educational knowledge, strong in second language skills and possessed of an easy familiarity with other cultures. No teaching certificate required.