If I could be the principal for the day at my school the five things i would do are below.
First, I would bring the whole school donuts because everyone loves donuts.
Next, I would give the whole school a free day to do anything because everyone would have tons of fun.
Then, I would do a basketball tournament with the whole school everyone would get into Groups and play because basketball is my favorite sport and I would be. Cool to see who wins.
After that, I would give everyone who one the basketball tournament a prize so they would be motivated to win.
Last, i would let school out early so everyone could do things after school.