I'm a high school teacher, so I usually leave my sharps and firestarters locked in the car trunk. I do carry a Leatherman Squirt S4.
Other things:
- EDC (Squirt S4, Cell Phone, Car Keys)
- Extra Medications (locked in desk drawer)
- Small FAK (School nurse has larger supply)
- 2-3 liter bottles of water
- few granola bars
- a few shelf stable meals with plastic utensils
On days when the students aren't there, I usually carry my Leatherman charge. The other teachers know that I'm the resident Eagle Scout so that I often have other tools stuffed in the bottom of the file cabinet.
Any other teachers want to share?