The student handbook is the closest thing private school has to a constitution

Most students never read the handbook until they're already in trouble. That's backwards. The handbook tells you exactly what the school can and can't do — and more importantly, what process it promised to follow.

If the handbook says students get a meeting with a dean before suspension, and you got suspended without one, that's your argument. Courts have held private schools to their own written policies when the school skips its own steps.

Public school students: your equivalent is the district's code of conduct, which is usually posted online and subject to state law on top of it. You have more outside protection, but the same rule applies — know the document before you're sitting in the office.

Pro tip: save a PDF copy of the handbook at the start of the year. Schools update them, and the version that matters is the one in effect when the incident happened.