I'm afraid the OP is stating just the start of attempted punishments / behavioral modifications that make little or no sense. The one common practice I always have to roll my eyes at are the "Zero tolerance policy" That's a school's way of needing to make judgment calls based on individual circumstances.

Example: I live in a largely agriculturally based area. Tim, 12 years old helps his dad with morning chores feeding cattle, barely finishing before hopping on the school bus, Tim fails to take his pocket knife out of his jeans that he uses to cut bailing twine. Later in the day a teacher spots the outline of his pocket knife in his front pocket. Zero tolerance, Tim is suspended for 3 days and carrying weapons is on his permanent school record.

In the example above there was no threat, only a hard working kid who made an honest mistake. The zero tolerance policy served the school, the community, and the student well didn't it? This is what happens when school administration does't wish to take the responsibility of making human judgment calls and instead relies on "Policy"