Time needed: 5 -10 min (one lesson involved)
Why? Everyone like to feel special once a while.
When? Any time students have birthday.
How? Install a ritual to praise someone in class at this special day. This method is clear a socialization and classroom management method. Those students could take special roles for that day, helping the teachers, being the leader in any decision for one day, celebrate the lessons in a small party situation. If you are forming this special days and including it in your lesson it is not only for the birthday child enjoyable, also for all other students its a break from normal usual rituals and a refreshment for your class.
Any risks? Don’t let those parties get out of control, its not a party replacing a lesson, its a lesson in party atmosphere.