Developing critical thinking is one of the factors that contribute to the quality of teaching in contemporary schools. To develop such skills, a variety of methods is required. Considering the methods and techniques used in fostering critical thinking skills in teaching, this study examines the use of a number of activities, both individual and co-operative, in a chapter of the Modern Greek Handbook about comprehension and production of written language. Furthermore, ways of self-improvement and improvement in a class level in terms of written language are shown using specific criteria. The goal of the suggested methodological approaches and activities is that students develop the appropriate abilities and skills to avoid considering information and opinions as given, but to be able to question and criticize them in order to form their own opinion and attitude.