Plans to leave Boston for a 3 night round trip to Vermont last week in September. Thursday thru Sunday, leaving late Sunday from Logan. Know it's a bit early for foliage but what would be my best bet.
Looking for best scenic route, don't have anything planned other than at least staying first night in Woodstock (reservations made but can change). How far north do you recommend me going? Any suggestions on places to stay? Greatly appreciate your advice. Don't mind longer drive if worth it.

Check Yankee Magazine's Fall Foligae Report 2017. It is predicting a good year for fall colors.

There is no best scenic route. I like rolling farmland along Lake Champlain with distant views of color. Some like higher elevations and granite cliffs. I prefer the Norwich Inn and the much smaller town of Norwich VT over Woodstock. I like the food at the Inn as well as the restaurant across the street (Carpenter and Main). The Saturday morning farmers market in Norwich is one of my favorites. There is music, great prepared food vendors and bakers, some vendors offering free samples, and lots of wonderful tastes of Vermont. It is festive and popular. A good activity instead of just driving around. (I also like King Arthur Flour and the farm stand on the same road as the farmers market.)

Yankee Magazine has a lot of foliage photos. Perhaps choose a scene you like and head there. Get a Delorme Atlas and Gazetteer for Vermont which will show you all the roads including unpaved ones and the location of interesting spots like covered bridges. Explore the cheese or wine trail. Rt 100 is popular and I would stop at the Warren Country store for lunch and to look at the mini gorge out back.

There are tinges of color here in NH already. You might not be too early this year.

To see foliage in late September I would head north to the Northeast Kingdom (St johnsbury north to the border) or maybe the north central mountains. Color probably won't be as far along in the Champlain Valley area. The leaves change first in higher elevations.

As others have suggested, check the foliage hotline info for current peak foliage info once you are here. This website suggests scenic drives
https://www.vermontvacation.com/thin...family/foliage

For festivals, etc see the tourist website
http://www.vermont.com/activities/fall-festivals/

One place in the NE Kingdom that has always looked interesting to me is the Derby Line Village Inn in the town just south of the Canadian border.

One of my favorite places near Woodstock is Plymouth Notch with the home of Calvin Coolidge.

Rt.100 from Woodsrock north has beautiful scenery and villages.

Day one -- Boston-Woodstock
Day two -- Woodstock to Plymouth Notch, then north on 100 to Stowe.
Day three-- Stowe to St Johnsbury via Craftsbury Common
Day four -- St Johnsbury to Logan via I-93 takes you through the western White Mountains via Franconia Notch. Spectacular scenery.

You absolutely positively need reservations for lodging for this trip. I learned this the hard way several years ago. Don't be like me.

Allow plenty of time on Sunday for return to Logan. This week there was a huge traffic backup north of Concord on both I93 and Mountain Road (alternate route) on Tuesday morning. We think it was simply construction plus commuters plus people who stayed over Labor Day to go home Tuesday morning. I89 from VT feeds into I93 south of Concord so southbound traffic can be stop and go on Sunday afternoons. I've seen the bus to Boston take Rt 3A instead of I93 from Concord to avoid the backup. Rt 3A can put you on I93 or I293 in Manchester.