What is a one-sentence summary of the following article?
Some schools have very structured policies regarding the consequences that a student should face for breaking the rules. Others have general guidelines, but give teachers more freedom to decide on the appropriate consequences. As you are establishing your classroom rules or contract, be sure to consider the policies that are already in place at your school, and make sure your classroom rules complement them.  Do not make exceptions to school-wide policies. For example, if your school prohibits all cell phone use, do not state in your contract that cell phone are allowed at certain times. In addition to outlining the expectations you have of your students, it is important to let them know what the consequences will be if they do not meet those expectations. There should never be any surprises when it comes to punishment. Make it clear if there will be a warning for the first offence. Keep in mind that this may be appropriate for some behaviors (like talking out of turn), but not for others (like hitting another student). Remind them that they signed the contract. Then have them identify which rule they broke. Ask them to articulate why this rule is important. Finally, have them identify what the consequence for breaking the rule is. When establishing rules and consequences in your classroom, it's important to be mindful about implementing them consistently. All undesirable behavior should be dealt with in the same way, whether it comes from the worst student in class or the best. Singling out "bad kids" will only make their behavior worse, so try to make them feel like they are the same as every other student in the class. Try not to focus so much on punishing students for bad behavior that you forget to reward them for meeting your expectations. Be sure to praise students for good behavior as well. Don't rely too heavily on external rewards, like stickers or pizza parties, as the students' interest in these rewards will eventually fade. The most motivating incentive for students to follow the classroom rules is the opportunity to be a part of a great classroom community.

Summary:
Consider the school's policies. Clearly outline the consequences. Refer students who break the rules back to their contract. Treat all students equally. Reward students for making good choices.