Do you have students who are distracted by everything? D you get tired of telling them to pay attention or don't get distracted? I have taught my first grade students to "not chase squirrels". I have this sign hung up in my classroom and they get a kick out of me telling them all the time to "not chase squirrels". In fact, they now remind each other to "not chase squirrels".
I would call this a success, try it out!