I don't disagree with your point, but I should point out that this: is quite unlikly.
If he lives in the US, I'm almost sure they'd go to that point. My old elementary school used to do stuff like this all the time, a kid wrote one non-vulgar word on the wall in the bathroom; the forced us to go with a teacher to use the bathroom, heck they made us clean the bathroom because the person that did it was in our own grade. Even my middle school does this from time to time, some kid threw a milk can out in the cafeteria, they checked all the security cameras and did not allow us to buy drinks the next day.
In the end, I would highly suggest not to do this. Yes, the chances to get caught are very unlikely, but if you do get caught (and trust me, schools have may ways, school tech support may not be that smart but district tech support are) you can guarantee your parents are not going to be happy, nor is the school, nor is the district. Your grades will reflect it and possibly your permanent record may reflect it.