Depending on what part of MA you are coming from, Erie PA would be near the mid-point. There are several good hotels at the Peach St. exit.

Second the Erie idea...makes for reasonable driving time both days.

Thanks, I'll look into that. We are coming from Western MA. I also wondered about driving on I-90 as opposed to I-80. Any opinions on what route is better to take. We're looking to make this drive as fun (if that's possible) as we can for a 7 year old.

If you take 90, and leave early in the morning, you could take a break and go to Niagra Falls at lunch time for an extra hour or so and then be at Erie for night time. Find a motel/hotel that has a pool and let her have a swim to get the kinks out.

If you go only in the US you will go through Chicago which has had a lot of traffic every time I went through. I do understand about taking a grandchild through Canada, I think you will not only need a passport, but a notorized letter from the parents giving you permission to take her out of the country.

Going from MA to Michigan will not take you through Chicago. Chicago is west of Michigan.

Right Pat, brain freeze

emalloy: good idea about Niagara Falls and Erie. I had same thought about the pool. Pat_in_Mich: any good thoughts for quick stop in MI on way to Traverse City?

Greenfield Village is fun but it's a full day so I don't know if you want to take that much time: http://www.thehenryford.org/

Frankenmuth is a cute town and we always enjoy a chicken dinner at the Bavarian Inn there:
http://www.frankenmuth.org/

You could visit the state capitol in Lansing if you will be passing through on a weekday although a 7 year old might be a bit young for that:
http://council.legislature.mi.gov/lcfa/capitol-tours.html

Detroit has a nice zoo which is actually located in the suburbs:
http://www.detroitzoo.org/

Not in Michigan but just south in Toledo, Ohio is the Toledo Zoo which I actually prefer:
http://www.toledozoo.org/

We drive every summer from Ann Arbor to Cape Cod. Took I-80 once and said never again. It is I-90 for us. When our son was younger we would stop at the Toledo Zoo on the way home. It is a lovely small zoo. Your granddaughter would love it.

Great ideas. The Toledo Zoo sounds like something we could do. Thanks all.