How long could I be in juvenile hall for this junior prank at my high school?

I'm going to be wearing all black and have a mask on my face to help reduce the risk of getting caught.I'm going to be in the 11th grade next year and I'm planning on sneaking in the school parking lot when no one is there because that's where the flag pole is. I'm thinking of getting my used underwear and running it up the flag pole. In the morning everyone will say "I pledge allegiance to my underpants. Is this a good prank? What are my chances of getting caught? I don't mind getting in trouble with the school but will they bring law enforcement to my school for this prank if I get caught? How will I get caught and how can I prevent from getting caught? Are there school officials there late at night or really early in the morning? What should I know before doin this prank? Also, how can I have all the students knowing I did this prank and not let all the staff know? Qould it be a good idea to put it on youtube? Do the staff and other law enforcers or adults go on youtube?

I don't have my name on my underwear so they're not going to catch me that way.

Based on exactly what you've posted?

Possibly Criminal Tresspass.
Definately "Wearing a Disguise in the Commission of a Criminal Act" (which can add significant time to a sentence, since in many (if not all) areas in the US it is a felony...)

For the actual prank itself, it would more be a suspension than juvie time.

No offence...but the last sentence is laughably stupid... Many of the people posting videos on utube ARE adults. Over 18's probably cover about 30-40%+ of the audience based on a number of videos watched in a sitting.

As for the rest of your questions...No. / Low to non-existent. / Any number of ways. / Depends on what's going on. / How stupid and/or infantile it will make you seem / You can't...someone WILL talk. / No, not really. / Yes...successful prosecutions have occurred because of such footage.

that one is juvenile and way over done.
that's the kind of prank you see in a kids show or something.
that's not worth getting in trouble for.

You think they won't notice your undies when they go out to raise the flag in the morning? If so, they are WAY too stupid to catch you.

Sounds like you are a juvenile hall candidate just for being kinda simple minded.........

if you use your DIRTY drawers then they can get DNA from your nasty crusty shorts. they dont need hair or figerprints

Okay, you have my answer of a good prank already. By the way, make it really look like an accident. Anyways, if you don't do something minor, than don't do anything. School codes are so overprotective right now it isn't funny. Anything you do could get at least a detention after school, if not an in-school suspension. Like said, do something that won't get you in major trouble if you do anything.

Wow. I think you would just be better off NOT pulling a prank, huh? Instead of worrying HOW LONG you would be in juvenile hall, why don't you avoid the situation altogether?

Thats all I have to say.