I'm thinking of printing 228 copies of a subscribe to PewDiePie poster on my school's printer.
Are you sure your PewDiePie poster was downloaded from a legitimate source?
I think I bought it off eBay.
While it is okay to be a fan of PewDiePie, it isn't okay to use your school's resources in order to advertise for him. You school has a limited amount of resources and they should go towards education and not entertainment and not be wasted. It would be a better idea to print your PewDiePie material at home using your own supplies.
What if I just stole the paper and ink? I am sure they have plenty.
You shouldn't take school resources for something not approved or needed by your school.