Critical thinking skills are an important topic of the United States' education system. This study examines the literature on critical thinking skills and defines them. The study also explores one specific teaching and assessment strategy known as the Socratic Method. The five-week research study used the Socratic Method for developing critical thinking skills in English Language Learners. At the end of the five weeks, ELLs developed critical thinking skills, therefore proving that the Socratic Method is an effective strategy for developing critical thinking skills in English Language Learners. Appendices contain details on three methods to recognize critical thinking skills: Socratic Questioning (Appendix A), Socratic Seminars (Appendix B), and the Holistic Rubric (Appendix C).