Jardin des Tuileries has a carousel, huge adventure playground and a trampoline park, plus a little boating pond where you can pay to borrow a little wooden sailing boat with a stick to try and keep it under control. The boats have interesting designs and inevitably float off to the middle of the pond and the fun is trying to chase it and get it back! There are also ancient water fountains to drink from.
I recommend Brasserie Flottes beside the Tuileries for a typical French lunch (they were serving aligot when we went, which is very cheesy mash!).
Tuileries is beside the Louvre and Musée d’Orsay if those appeal, or lots of shops and a big shopping centre by the Louvre!
I went to the Musée de l’Armée at age 7 and there were some fascinating artefacts, plus Napoleon’s massive tomb. Usually easier to get into than the Louvre.
Choco-Story Paris is also fun, tells the story of chocolate including genteel ladies drinking from special cups. There are dispensers of free chocolate throughout the galleries to stuff your face learn about the range of flavours. We went last year and there was a kids’ trail of Playmobil scenes, if they got all the answers they got a chocolate lolly. They also do demonstrations at the end.
I always like visiting a patisserie and picking something beautiful. Gerard Mulot does good flavours.
Depending how vegetarian you are, le Pied de Cochon (pig’s foot) is a 24 hour restaurant serving traditional food but also pig’s trotters, and the door handles are brass pigs feet. The Vacherin dessert is made to look like a cream and meringue pig, and they gave us all a small meringue pig’s face to eat!
If staying a while, there’s a rechargeable Navigo pass for public transport you can buy, it needs a passport sized photo and can be bought at a counter. Makes it a bit easier to get around compared to carnets or similar.