This study tries to describe the method by which Design Thinking, a dynamic, innovative model of problem-solving procedure for the challenges of our time, can be adjusted to the modern school language curricula and make language courses meaningful and interesting to secondary students. Design Thinking (DT) traditionally originated from architecture, design and the world of enterprises and business, has given educational environments (schools and institutions) up to date pedagogical tools to reframe the way they prepare students for modern societies. The author and secondary teachers' coordinator/trainer made an effort first to adjust the Stanford DT five working stages in Greek language curriculum and courses and then train secondary language teachers accordingly, so as to implement DT in real life school settings. This effort comprised seminars and a main training workshop, regular contact with the schools and the participant teachers' attitudes' investigation. So, the final purpose of the study was to explore the main impact of the DT classroom application in Greek language lessons in the basis of advantages and disadvantages, as there is a need for further work and research in the field.