Teaching, as a profession, is becoming more and more challenging every day, not only because the teacher has to deal with unpredictable difficulties in constantly changing uncontrollable cultural and social contexts in the classrooms, but also for the need, nowadays, to be a curious explorer, a systematic investigator, and a creative innovation to solve his/her problems while teaching, using a flexible, self-reflective, critical, and production-oriented approach. Educational Action Research can provide a chance for the teacher to develop his/her critical thinking skills to become effective self-reliant problem-solver to the actual unique challenges that no one, but him/her, can better understand and administer in the classroom. Thus, s/he becomes enthusiastically involved in structuring and sharing a more comprehensive view of education. This paper investigates the possible outcomes of using action research in education, with an emphasis on teachers, after highlighting main critiques. It starts by discussing first the early evolution of Action Research both as a notion and a structure. Then, it reviews primary literature and research findings on the benefits of using Educational Action Research for teachers. The paper suggests that taking the role of teacher-research may help in achieving sustainable development at the level of the classroom and contributes in promoting the professional careers of teachers.