Be positive around your students. You are a role model to your classroom and have great influence on the students' behavior. If you are positive around your students, they will be positive as well.
Reduce problem behavior by keeping children near socially responsible peers. This will help increase positive interaction between students and decrease problem behavior.
Use physical positive reinforcers to help increase desired classroom behavior. Common physical rewards are healthy snacks, stickers or toys.
Give internal rewards to promote positive behavior. Some examples of internal rewards are publicly praising desired behavior, sending home positive notes to parents or allowing children the opportunity to be teacher's helper.
Establish a class routine early and practice it over and over again. It takes preschool-aged children a while to learn new routines, but once they do, it will help create a more positive mood in the classroom.