Suggestion for day from Paris

Chantilly, Fontainbleu, and Versailles are all very close and worth a trip.

Another possibility is the Champagne region. You could easily visit Reims and Epernay and tour a couple of Champagne houses in a day trip. The tour of the caves at Moet et Chandon is particularly interesting. The cathedral of Notre-Dame de Reims is very historic; it's where the kings of France were once crowned.

In addition to the good suggestions so far, Vaux-le-Vicomte is fantastic, Malmaison (Josephine's home), renting bikes in Giverny and seeing Monet's home and gardens as well as the charming town, renting bikes in the gardens at Versailles and riding all over is also very fun. There's also a town called St. Germain-en-Laye, right outside Paris and a very easy RER ride. Charming, upscale town with a chateau.

We took our kids on the Eurostar to London for the day and they loved it! Boat cruise, Tower of London, Big Ben, etc. It's really easy to do! A totally different world from Paris...That said, Normandy is wonderful too, but I would definitely rent a car...very easy driving around.

I was thinking about that! Did you do it on your own or use a company? Taxi around London or walk or subway? Thanks!

With only 5 days in Paris I wouldn't suggest a London day trip. Too much travel trouble for a short time in another overwhelming city. See London on a separate trip when you have time to do it justice. Normandy may be too much for a day trip also, I know I wouldn't do it. I think Giverny, Versailles, and Fountainebleau are good ideas. Another choice is Chartres, with an easy train (from Gare Montparnasse) that takes you through some of France's breadbasket wheat country. The cathedral there is magnificent (as is Reims, in the opposite direction from Paris).

With a 7yo, I wouldn't consider a day trip much bigger than Versailles, although Giverny might be okay. I've been to Reims and Epernay with my kids and we had a good time, but there really isn't much for kids there. The Cathedral at Chartres is under serious renovation and more than half the interior is covered by scaffolding. Not that it would interest a child (I found it boring in its current state.) Normandy can be interesting for kids, but I could never imagine doing it in a day trip. If you don't see the chateau at Versailles, then you could come to Fontainebleau to see the chateau, or go to Vaux le Vicomte (which will let you rent a costume for your daughter to wear during her visit - fun for kids). But Vaux-le-Vicomte is hardly worth an entire day trip.

You could take the train to Tours and then get on one of the tour buses from there and see the chateaus.