6th Arrondissement with 2 children

I'd think that 3 bedroom apartments are equally expensive in the Saint Germain part of the 6th as they are in Les Marais so you may want to look closer to Montparnasse. Are you getting three bedrooms so that each of the children can have a room?

I was wondering the same thing. Anyway they can share a room...it would likely be a big savings for you.

3 years ago I stayed in the 5th at apartment Le Lutece with myfrancevacationrentals.com
I was very pleased with it. Bus stop right outside the door, maybe a 15-20 minute walk to Luxembourg Gardens. Near rue Mouffetard, a wonderful market street. There were 3 of us sharing the place. Quite a bit of room. 2 bedrooms; the bedroom with 2 singles has them separated by a bookcase so there is a bit of privacy. A tiny elevator that I only used with my luggage.

You have the Edgar Quinet Market in Montparnasse on Wednesday and Saturday mornings.

Look at homeaway.com, vrbo.com, and other rental sites you can find via Google or using the search function for this board, and see if you can find a desirable affordable place in the 6th or elsewhere. The site should provide a map showing at least the approximate location. Then use the "street view" function on Google Earth to eyeball the streets around your candidate locations. Chances are you will find cafes, restaurants, and stores pretty much everywhere, at least within a block or so. You'll also get a better idea about traffic, sidewalks, and other neighborhood features.

Three-bedroom apartments won't be cheap, especially on lower floors or in buildings with elevators. (Remember that the "first" floor in Europe is what we'd call the second.) You'll have more choices if you can get to two bedrooms. In general, farther from the river will cost less, other things being equal. While the Luxembourg Gardens are wonderful for kids (of all ages), Paris is filled with little parks and playgrounds in most neighborhoods. You might want to be somewhere further out, like the area around Place des Nations or the Porte Doree, with wide sidewalks and lots of trees.

I just returned from Paris with my 7 year old. We had a home exchange with a family in the 5th (Latin Quarter) near where June described above. It was a great area and worked well for our family. You should note, we never ate out for dinner in Paris, only lunch. There were very few (if any) children in restaurants -- even cafes-- during dinner. We still had wonderful meals (and more affordable) at lunch. Our daughter loved Paris! Enjoy your trip!

Recent changes in the vacation apartment industry in Paris will likely affect your ability to rent an apartment in April.
A new law was passed in July 2016 that will require anyone listing short-term apartments on the internet to include a City-generated license number. You might inquire about this before you send in your deposit.

A three bedroom apartment !! wow.. seems to me you are already in the "expensive " category just by wanting that much space in central Paris..

The 6th is literally filled with shops. cafes, bakeries. .etc.. so staying anywhere you are no more than a 1/2 block to something.. and the park is nice for kids( and adults) if weather cooperates.