The three-person I-Team of the Boston's Housing Innovation Lab has quite the challenge -- keep Boston a city that isn't just for the rich and the poor -- and places that the working middle class can still call home. Funded by a three-year $1.3 million Bloomberg Philanthropies Innovation Team grant, the lab is guided by a planner, an educator and an artist -- an intellectually diverse team assembled to address the challenge of building and sustaining housing in Boston for middle-income working families. There are two co-chairs: Susan Nguyen and Marcy Ostberg. Nguyen was program director at the Mayor's Office of New Urban Mechanics, which houses the Housing Lab. She has a master's degree in urban planning from the Harvard School of Design.