For my kids:

Invalids Army Museum -( lots of armour and weapons)

Louvre- Egyptian Section and Medival Louvre, Napoleons Apartments and Crown Jewels

Towers of Notre Dame

Arc De Triomphe( nice view of streets)

ET - of course( my son enjoyed taking the stairs neat perspective

Catacombs- highlight for my boys who were 13, my daughter at 11 chose not to go

Bike tours, Fat Tire

Shoah Memorial( we have nothing like that here)

Versailles , particularily Marie Antionettes Hamlet

Chantilly, having strawberries and Chantilly cream in the garden cafe, and the horse museum and Royal Stables in particular

Luxembourg and Tuilleries Gardens( playgrounds)

Riding the metro, my kids liked it.

Riding the HOHO buses, they liked the break( from walking ) and the views..we sometimes pick up a snack and use the time on the bus to munch while enjoying the birds eye view of the neighborhoods

Paris Plage, its only in summer, but its fun for SMALL kids, my older kids were not impressed.

Ice cream, every day in afternoon.

David Lebovitz has some fine ideas here:

http://www.davidlebovitz.com/2009/04/ten-great-things-to-do-with-kids/

What a great idea !!! Thank you .. I promise to add to it once I've been

Thanks to those who responded so far... I'll check out David's ideas. I love his blog.

Though I've only been to Paris as an adult, I'll add the things I'm most looking forward to doing with them when we get there in May. We'll be there for 10 days, so we are keeping our plans simple and looking forward to plenty of down time, "just hanging out"..., lots of walking, eating Pain au Chocolat, fabulous cheese and bread, and staring at the Eiffel Tower.

Here's a specific list, though I'm sure it'll grow.

1. Wander through the Musee D'Orsay... several times.
2. Picnic at the Champ de Mars.... under the gaze of the Tour Eiffel.
3. Go up the Tour Eiffel.
4. Take a daytime boat on the Seine. I've never gone myself, but I've heard it's a great thing to do with the children and a different way to see Paris.
5. Marvel at (then sample many of) the pastries in Gerard Mulot and a dozen other patisseries. Rinse, repeat. Pain au chocolat, anyone?
6. My 10 year old really wants to "shop" in Paris... so I'll probably venture at least once into Galleries Lafayette but we'll probably end up in the street markets so she can find an eiffel tower keychain for her backpack. (kids are easy to impress)
8. Centre Pompidou, if only for the outside of the building
9. Buy them a streetside crepe and ice cream at Berthillon. (I know, it's cliche but they are so excited)
10. Notre Dame... for the stained glass especially
11. We'll probably venture at least once into the Louvre for the decorative arts. The kids want to see the ornate furniture and "jewels". My 6 year old wants to see "the naked statues" in the Greek section, and my 10 year old wants to see the Mummies. So we will do a very edited version of the louvre during our trip.
12. Versailles. We'll trek at least once to Versailles as a day trip. I've heard it may be better taken in as 2 short trips.
13. Ride the ornate turn of the century carousel at the Luxembourg gardens by the kids playground, if it's still there.
14. Shop often in any number of the markets (Rue Cler, Buci, and Avenue Saxe) for food and other goodies.
15. We *might* if I can convince my husband visit Monet's house and gardens. I think the kids will enjoy the day trip... my husband thought it is kind of a boring tour.

Would love to hear more ideas.

Thanks!

My nieces' (18 and 21) favorite activities last summer were:
1. Night Segway Tour (Fat Tire)
2. Sunset boat ride on the Seine (Vedettes Pont Neuf)
3. Pizza and wine picnic on a park bench in front of the Eiffel Tower
4. Shopping - grand magasins and surrounding streets; Rue de Rivoli; St. Germain
5. Gelato at Amorino
6. Any photo-op of them with the Eiffel Tower in the background
7. French onion soup and escargot at Au Pied de Cochon
8. Riding the Velib bikes

Skatterfly, for stained glass , go to St Chapelle on a sunny day, swear to you, it is a jewel box. Lines can be long, and sometimes even with the museum pass they won't let you skip them if its busy, so go when if first opens.. its small, but it is magical. Its right by Notre Dame so easy to combine.

Tracilee, I agree with your neices, best gelato in Paris is at Amorinos and they make into these pretty "rose petal " cones..

I'm adapting an idea I just saw in the Paris 100 thread: to bring a sketch pad to the Louvre or D'Orsay (or for that matter the bridges or Notre Dame or to the Champs de Mars or anywhere in Paris). My kids both love to draw and sketch what they see, so I'll pack small sketch pads and pencils in my day pack. Maybe they can sketch their favorite attractions while mommy and daddy stop somewhere romantic for a glass of wine.

Oooo, this is great! Marking as I'll be there in April with my 11 & 7 year old sons!

Keep the ideas coming!

I'm a broken record on this: Chateau de Vincennes. Really cool castle, just a metro ride away. I haven't done a comparison, but suspect it is more interesting to kids (including this older "kid") than Versailles.

My kids liked walking up the Arc, and down from the 2nd to 1st tier of the Eiffel.

I think they thought the sewer museum was ok.

They weren't too excited about onion soup, but did like Croque Monsiuer/madams.

Also, pizza, gelato and crepes (nutella!).

After the Louvre, they enjoyed a little sitdown at the pond in the Tuilleries.

Hot chocolate at Angelinsa's.

For inexpensive gifts/ souvenirs for the kids, try Rue de Rivoli’s columned promenade--behind the Louvre with the Tuileries Gardens lining the other side of the street.