Make a classroom elf of your own, or use this as an individual behavior modification technique and have each child make one. The body is made out of a decorative lunch bag. Children add tally marks for staying focused, completing tasks, behaving etc.
A "makes your think" poster that can be used as a writing prompt. "Is this advice true? Good? Why or why not? How can changing places with someone help you understand them better?" This is a great poster if you're doing the "Fill A Bucket" program.
Two posters to alleviate interruptions while you teach. If a child signals by displaying the appropriate number of fingers, you can tell at a glance what they want. You also don't have to say a word. Simply make eye contact and nod yes or no.
A nice reminder to students to take responsibility for their actions and get their work done to their best ability. This would make a nice jump-start to a writing prompt about the above. "You get what you get, so don't get upset!" is a rhyme that I teach my students early on. It helps alleviate "melt downs" when children don't get their desired choice or color preference. This poster too, is a gentle reminder. You'll be surprised how your students will recite this, when someone is having a minor "meltdown".