I think graffiti is a bad thing to do on campus because the school would look very ugly. How would you feel playing on a basketball court that is painted with words and pictures all over it? Do you think teachers would want to teach at a school with graffiti all over it? No way. So since someone wanted to spray paint the basketball courts, you do not have a lot of fun and you do not get a good education.
There is also the risk that you might get caught. I heard that if they catch you doing graffiti on campus you could get suspended, and it is true. I know what you are thinking, how I am going to get caught? When they find graffiti, they have cops trying to find out who did it. You would never make it away from them. Why ruin your life just to try and be cool?
So, what if you do not care about your life? Think about the person who has to clean it up, he might have kids and he needs to get home to them, but instead he has to stay and clean it up. Would you like it if you were in that situation? Would you like to clean it up? I did not think so.
After all that happened because you decided to paint a basketball court, you affect 3 peoples lives, your friends lives, your life, and a janitors life. So please do not do graffiti because in the end it is not cool at all.