I'm thinking of pulling some numbers from my own imagination and adding them to the report that I intend to publicly release
Would you really falsify numbers by adding your own made up to the official ones in the upcoming report?
I plan to report my school's administration about how they treat their students.
Then you should be honest in your work, you are breaching your contract by lying about whatever data you report. Your report will determine what happens to the school, and faking numbers to make them look better or worse is going to impact the students the most.
Since when did you become a lawyer?
It doesn't take a liar to know that falsifying data is wrong. The schools administrators hired you to do a certain job correctly. If someone finds out the school could get in trouble and you'd be fired.