Classroom climate is the key context that facilitates or complicates the learning process. Peer relationships are some of the principal determinants of this concept, especially for adolescent groups. Analyzing the classroom climate deeply in terms of peer relations can be vital in understanding the students’ continuity, success, and connection with the classroom and school. The objective of this research is to make an in depth analysis of peer relations in two classrooms with different climates: positive and negative. In accordance with this, two classrooms with positive and negative climates were chosen through the “classroom climate perceived by students scale:” over a 72-hour period, two different classrooms’ lessons were observed. 18 and one teacher were then interviewed. According to the findings of this research, in the classroom with a positive climate there were more positive and negative behaviors in terms of frequency observed and diversity of behavior. In the classroom with a negative climate it was observed that the interaction was more limited and the frequency of behaviors categorized as negative was higher than the positive ones. The findings were debated through “cultural reproduction theory,” “resistance theory,” and “functionalist theory” in the framework of “hidden curriculum theory.”