How can i annoy my stupid bitch boss?

I work in a public school district and i visit about a dozen different schools. Bosses are making us share our calendars, thinking they'll be able to track us and catch us doing something wrong. I'm planning to add "started my period" every couple of weeks. Are there other good outlook tricks to fuck with them?

ETA- This is my work calendar, not my personal calendar. I know that seems reasonable but it's being done as a petty micromanagement tactic. There are about 20 of us in my department who drive from school to school every day working with kids with physical disabilities. They don't just want to know when we're in meetings - they want every minute of our day to be accounted for - 8 to 830 school A, 840 to 11 school B, etc. I go to 14 schools. If my kid at school A is absent or if i get a call from school J that i need to stop by to fix a wheelchair, am I supposed to pull over and update my calendar so they can find me? I could spend an hour a day in parking lots editing my calendar. Most days i eat lunch in my car between schools. Last year they made a rule that we can't carry to-go cups because it looks like we have enough free time to drive thru Starbucks. It's just to be controlling.