I found this idea shared by Shannon Popkin in the July 2008 Focus on the Family Magazine and I absolutely adore it!
Over the summer your children plan, prepare, and serve a luncheon to last year's teachers, with your help of course! This can include school teachers, music teachers, Sunday school teachers - whoever they want! Kids get to practice hospitality and learning to serve others with a cheerful heart while getting a chance to see those beloved teachers again. Teachers get a chance to have a nice lunch and relax!