I don't do anything for those under age 2 because I don't want to detract from what the parents are doing. ie no cupcakes with candles etc. That is for the parents to see the child's reaction to a candle, blow it out, face in the cupcake etc. For those 3 and up I let them choose the lunch for the day - often a choice of A or B not just a random pick and we have something special such as cookies with sprinkles or ice-cream. Parents sometimes send cupcakes and I just serve them at snack if sent not making too big a deal out of it.

For gifts I usually give them a book.