On the border of Massachusetts and Rhode Island lies the John H. Chafee Blackstone River Valley National Heritage Corridor. The National Park Service’s Heritage Corridors and Heritage areas are a loosely associated sites both natural and historic that tell the story of an area or series of events. This site deals with the advent of the industrial revolution in America and preserves the main attractions in the Blackstone River valley dealing with that. In 2014 President Obama established the Blackstone River Valley National Historical Park which will encompass most of the sites of the corridor.
The NPS has a great full day itinerary for visiting the corridor and I recommend you use it as a guide. The sites are not contiguous so you will need to drive from one to the other.
Samuel Slater founded a cotton spinning mill in Pawtucket, RI which is a good starting point for your road trip.
In addition to the historic buildings and visitor center / museums there are a great many pleasant natural areas that are perfect for an afternoon picnic.
Just a short distance from Boston this is both an educational and relaxing way to spend a wonderful day in the New England countryside.