The Algerian educational system is competency-based; therefore, it focuses on developing learners' competencies and skills through a learner-centered methodology that fosters autonomy. To help teachers apply such methodology, the English syllabus designers recommend using Project-Based Learning, active learning, and problem-solving strategies to help learners develop 21st -century skills and communicate effectively, collaborate, and think critically and creatively. However, those methods and strategies are absent in classrooms, and therefore critical thinking is not promoted. In this context, two questions are raised to affirm this hypothesis. (1) To what extent do teachers respect the syllabus designers' recommendations? (2) Why do teachers avoid using the recommended methods and strategies? To investigate those questions and achieve the aim of this research, the researcher carried out an in-depth quantitative analysis of 30 anonymous classroom observation reports written by a certified English teacher trainer. To address the qualitative aspect of the research, the researcher held a semi-structured interview with the same teacher trainer. The reports that were examined contained 150 comments on teachers' classroom practices and assessment methodologies. The results showed that English teachers partially respect the syllabus designers' recommendations. Besides, the teachers' methods, classroom practices, and assessment approaches are mainly based on direct instruction and language content acquisition rather than on reflective and problem-solving learning; therefore, they are not conducive to implementing and developing learners' critical thinking. The conclusion drawn from the data analysis of the current research is that teachers' hesitance to use the recommended pedagogical approach and methods is due to some hindrances faced by teachers, namely classrooms overcrowdedness, the content-based baccalaureate exam and lack of time due to the lengthy English programs.