Count down before breaks to avoid "just one more thing" negotiations.

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Ideally students will be focused on problem solving when they are in the computer lab. Show respect for students and their problem solving by giving them a warning before you ask them to stop working. You can count down from 5 or 10 before stopping the class. When possible give students a 5-minute warning before the end of class and a 30-second warning before an announcement. These strategies can help reduce students’ negotiations of needing to do “one more thing.”

Example: "We will have monitors off in 30 seconds."

See this and related tips as a Tip Sheet: http://csteachingtips.org/tips-for-lab-rules

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