As a lawyer married to a school super. I have to say a few things. This stunt will prove nothing to anyone but yourself. Even if you do pull it off, you should never tell anyone. Don't take any photos or videos. If your school is monitored by camera, you still can be tied to the location via tracking. Also janitors are to inspect every inch of school grounds weekly in order to look for oddities such as people living in the school and safety/fire hazards.
Also once every 3-4 months a full fire inspection is done, and every 4 months general inspection takes place. This includes pest/asbestos/radon inspection.
Listen you have no idea what goes on in the school after hours. Please be aware that every in h of that school gets inspected.
Now as a lawyer, once this is found the first thing that will be done is a crime scene will be established. They will go over the area with a fine toothed comb. This will also include video investigation, which will help narrow down the culprit. I can garauntee that if found it will be easy to link this to you.
Now depending on the state, cultivation laws vary, but the judge will come down extremely hard because of your disrespect for law. Also the fines that your family will endure are astronomical. Endangerment and all sorts of lovely things will be brought against you.
If you do this, you are dumb and have no respect for the "culture" yourself and your family.
Do me a favor, and get some friends and plant some sunflowers in the middle of a ball field.
Continue going to school and graduate. Then go to college, go into law and fight the fight from the inside.
Doing this proves nothing.
Remember there is a time and place for everything, and it's called college.