Students, staff, spouses and children enjoyed socializing at the Pierce Building Fall Social on the evening of November 14. In the spirit of innovation, students and children designed and built balloon-powered Lego cars, and tested them for distance in the Building 1 basement corridor. A car made by graduate students placed first, having moved steadily and smoothly farther than all the others. Working steadily on an original design, the 10-year-old and 8-year-old sons of Jeremy Gregory, executive director of the MIT Concrete Sustainability Hub, placed second, edging out a double-balloon powered vehicle also by graduate students.