Greenfield Village is a wonderful day trip for those with children that are a little bigger.  Our 4 year old enjoyed it but it wasn't really her thing, she wanted to go on the carousel etc.  A nice place to learn about the history of many different people, see the Wright brothers home, see how glass is blown and so on.  It is a great experience for those of all ages.  It is now a lot more pricey than it was for just the Village you can expect to pay $20 per adult, plus parking and for children over 5.  Also the ride passes are $10 a day per person a bit steep in my opinion but you can do the Model T, Boat, Carousel and train.
                        
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