Let’s Build is a family volunteering initiative bringing engineering into Needham’s elementary schools by training family and community volunteers to support classroom design challenges.  Its major fundraiser, the Let’s Build Engineering Extravaganza, will be held January 30, 10AM-2PM at the Needham Science Center within Newman Elementary School (1155 Central Ave. in Needham).  Activities include a take-apart table, catapults, demonstrations by Needham HS robotics, an egg drop, Olin’s 3D printer, bridge construction, a cantilever challenge, kite-making, and interaction with local scientists and engineers.  Admission is $5 per family (or free for volunteers and their families).