This article discusses the rules science teachers need and how to implement these rules in the class. What should my science classroom rules be? Ideally, this question is asked prior to the teacher's entry to the classroom during their teacher training and revisited throughout their coursework preparation and student teaching. A science teacher needs to have rules and routines in the classroom that support a positive and safe learning environment for students throughout all classroom activities. For teaching science, a teacher needs to have two types of rules: ones for general classroom behavior and ones for safe laboratory procedures and behavior. These two work together. Rules and routines for the appropriate use of these materials can be satisfied through general classroom behavior rules that address the need for students to be respectful of each other, and classroom and student property. Rules for safe and appropriate use of science equipment and supplies must be established to protect students from harming themselves or others, safeguard against damage to equipment, support the ethical treatment of living organisms in the classroom, and protect the environment at large. New science teachers need multiple examples of general classroom rules so that they may become familiar with the scope of rules that exist and the ways in which they are stated for increased student understanding and adherence. The authors recommend two other resources for all new science teachers to become familiar with. The NSTA's "Position Statement on Safety and School Science Instruction" (2000) briefly outlines general school laboratory safety considerations and is available online. More specifically, the authors recommend becoming familiar with Chemical Safety for Teachers and Their Supervisors (American Chemical Society 2001), which is also available online and provides critical information for setting up a safe laboratory environment. How can teachers get students to follow the rules? Ideally, this question is considered as new teachers develop their rules for use in the science classroom. This question should be considered prior to the new teachers' entry to the classroom during their teacher training, and revisited throughout their coursework preparation and student teaching. In order for a new science teacher to have a safe and positive learning environment for students, the teacher must establish classroom rules for general classroom behavior and a separate set of rules for safe laboratory procedures and behavior. (Contains 2 notes.)