My friend is a school teacher and every year I help her make items for her room. This year she had found a tip on Pinterest about making a Warm Fuzzies Jar. It's a great way to encourage the kids to work together and be kind.
The concept is simple: every time the kids are good listeners in class, well behaved in line or at lunch, follow directions well, or are caught doing something good for a classmate they gat a "warm fuzzy" (aka pom pom) to put into the Warm Fuzzies Jar. If behavior is noticeably bad, you can opt to remove a warm fuzzy as a consequence.
Once the jar is full of "warm fuzzies" the class gets to enjoy a reward. It could be an ice cream party, pizza party, pajama day, etc. It's a neat way to talk about how doing good things makes people feel. The teacher gets the "warm fuzzy" from the good behavior and the students get them from making their teacher/classmates feel respected and appreciated.