I absolutely Love Mackinac Island. What a great place to bring kids. A small area with no vehicles and you have to get around by walking, biking, or horseback riding. With that being said, I for one thought Fort Mackinac was pretty cool, though I could see where younger children would not enjoy it. You really need to understand history somewhat to truly appreciate this, so if you have older children by all means go, otherwise stick to outdoor fun for the little ones.
If my kids were doing a history report this would have been great, but the hill to get to it is really steep so there was lots of complaining. The rooms to see are O.K. Not really impressed but I guess they were living under harsh conditions. The island itself is really great and their are many things to see without making the trek up the hill.
Our family had younger kids with us, and this was not the best place for them. For 8 and older, this is a fun place to explore and learn some history. The best part is the demonstrations and reenactments (court martial, firing of a cannon, dancing). The view across the water is also beautiful. There is a small restaurant here run by The Grand Hotel. It is overpriced, but a lovely spot to sit and enjoy the view. Touring the buildings is ok. Some of them are empty. Others have exhibits or are finished with period pieces. Depending how interested your kids are in history, you can spend at least a couple of hours here.
We relly love Mackinac Island, and Fort Mackinac is a wonderful spot to visit there. Its really interesting to see how a beautiful resort island was once an important military fort. The island is a very special place, no cars, so you ride bikes or horses everywhere. The lake is so beautiful and once away from all the tourist, its a very serene place.
I have been visiting Fort Mackinac since I was a kid. The kids and I love watching some of the live military demonstrations and fiting the cannon. There is a lot to learn about the fort. It is fun to wal into each of the buildings in the fort and take some good pictures. Admission is free for kids 4 and under.