From I-91 North or South, take Exit 48, the Elm Street Exit.  From the south, you will turn right off the exit ramp.  From the north, turn left off the ramp. 

You will pass the Westfield Shops (mall) on your right, and about a half-mile later, Asnuntuck Community College, also on your right.  Shortly afterward, the main road bears left.  Here it becomes Shaker Road.  Stay on the main road and about ¼ mile from the fork at the next stop light you will see Henry Barnard School on the left side.