The students on the bus were excited about what their community service activity was going to be. It was a chilly morning — Martin Luther King Day — and the buildOn students at John Hancock High School were up early to participate in the annual Chicago Cares Celebration of Service event. Each group was assigned an activity once they were on the bus. Hancock’s destination: a senior citizen’s center. The activity: bonding, playing puzzles, serving food and planting herbs with the seniors.