We develop our classroom rules together, this way the students are more invested in the rules. I usually read the books, The Recess Queen and Enemy Pie, a couple of days prior to establishing our own classroom rules. We talk about why we have rules, who makes rules, etc. Once the students decide they are willing to follow the classroom rules, they are invited to sign the poster, sort of like a classroom contract. In the past, I have also had students paint their hand and use that as their signature on the poster.