Random Acts of Kindness
Kids do many kind things, and many go unrecognized. Setting aside time to emphasize those kind things can beget more kindnesses; kindness models kindness. Introduce to students a form on which they can submit the name of a student and a kind act that he or she did in class, in the lunchroom, on the bus, or on the playground. Each week, draw two of the “random acts of kindness” submissions from the stack and recognize those students in a special way. If the name of a student who was recognized in the previous month is drawn, you might get students to agree that someone else should be chosen in place of that individual. As a reward, a certificate is great; a simple reward token just adds to the honor. Post the certificate in the hallway or classroom. Then watch how many kindnesses start to be done and nominated.

Source: Schoolnotes.com