For 21 years, Jeong Sung-Yoon worked as an English teacher in middle and high schools. he is currently serving as the principal and IB coordinator at Daegu Joongang Middle School for three years. Since 2016, he has been striving to improve efficiency and practicality in the educational field by applying customized IT (Google) EduTech tailored to the revised curriculum base, and lecture nationwide though various educational activities such as middle and high school textbooks, reference books, and has been focusing on constructing and implementing the school curriculum as an IB (International Baccalaureate) MYP World School Coordinator, and is always working to improve the efficiency of cloud-based education and teacher evaluation expertise.