The classroom teaching atmosphere in American universities is usually described as active, interactive and encouraging students to participate. Teachers usually use a variety of teaching methods, such as lectures, group discussions, case analysis, experiments and so on. To stimulate students' interest and active participation.

In class, teachers encourage students to ask questions, express their views and share experiences. They usually establish an open learning environment for students to express their views and ideas freely. Teachers will also actively respond to students' questions and conduct in-depth discussions and exchanges with students.

In addition, American university classrooms also focus on cultivating students' critical thinking and problem-solving ability. Teachers will guide students to analyze problems, put forward assumptions, collect evidence and conduct reasoning. They will encourage students to think independently and cultivate their innovative and critical thinking ability.

In addition, American university classrooms also pay attention to students' cooperative learning and teamwork. Teachers will organize students to carry out group projects or team work, so that they can learn to cooperate with others and solve problems together. This cooperative learning method is helpful to cultivate students' communication, cooperation and leadership ability.

Generally speaking, the classroom teaching atmosphere in American universities is positive and interactive, encouraging students to participate. Teachers stimulate students' interest and enthusiasm in learning through various teaching methods and activities, and cultivate their critical thinking, problem-solving ability and teamwork spirit. This kind of teaching atmosphere helps students to develop in an all-round way and achieve better learning results.