Welcome to the Midwest! St. Louis is a great city for family vacations. I live on the other side of the state, but have visited St. Louis several times--none particularly recent, but here's my thoughts:

--Here is a riverboat cruise link: http://www.gatewayarch.com/experience/gateway-arch-riverboat-cruises/

It's not something we've ever done, but it does look kind of cool--an hour would probably be enough time for kids the ages of yours

--Highly recommend Grant's Farm--your guys will love it. Free, but you need to make reservations. Usually there are Clydesdales there I think.

--St. Louis has a transportation museum and my DS loved it when he was that age: http://transportmuseumassociation.org/

As for Branson, Silver Dollar City is really nice. The first time I went I was surprised at how pretty it is. They have a cave as part of the grounds there so if you can check that off if you want. The owners of SDC also have a water park and a more traditional "amusement" park. Branson has lots of independent (i.e. not chain) motels so it can be kind of overwhelming to sort through. Hopefully someone on here who has been there more recently can help with that.

musicfan - thanks for the info on the transportation museum. my boys would love that. hadn't come across that yet. and yes, the choices in branson are overwhelming. i don't know if we should stay in branson itself, or on the lake (tabletop???).

Tablerock Lake. Stay in Branson, it will be more interesting for the kids and your parents. There is an airport near Branson now that has some national flights and of course the Springfield airport, in case you don't want the long drive back to St. Louis. Your children might enjoy The Magic House & the Children's Museum in St. Louis.

Slw - thanks. i've discovered flying to the midwest is expensive! it's going to cost us more to fly from boston to missouri than it did to travel from boston to california! st. louis saves us quite a bit of money, so we'll at least fly IN there, but maybe we'll go out of springfield. and i'll check those places out now. thanks again!

Look at the possibility of flying out of nearby Springfield rather than going all the way back to St. Louis. You can actually fly out of Branson itself but connections aren't as extensive vs. Springfield.

I think that transportation museum gets overlooked a lot so that's one of the reasons I bring it up when applicable. DS is now 20, but he loved all kinds of vehicles as a little guy and he LOVED that museum.

Also, kind of on your way out of St. Louis going to the Branson area is: http://www.purina.com/purina-farms/purinafarms.aspx

It doesn't really take the place of Grant's Farm (it's a completely different kind of place), but it was a fun enough stop.

I've not stayed in Branson, but I live in St. Louis. Staying at the Drury downtown will be fine for seeing the Arch, the river boat cruise, and the City Garden on foot. The weather in April can be iffy though - some days are beautiful and springy, then the next it's chilly and rainy or even snowing. I'm sure you can relate being from Boston.

Forest Park is a short drive from downtown and has the Zoo, the Missouri History Museum, and the Science Center, which your little ones might enjoy also. http://www.slsc.org/

Not sure if you meant "City Museum" instead of "City Garden," but if not, I'd definitely recommend seeing the City Museum if you have kids -- it strikes me as a really fun place for youngsters.

The Missouri Botanical Garden is another St. Louis option not mentioned yet which may hold appeal to older and younger folks.

For places to eat, consider The Hill neighborhood for Italian food, as well as eateries in the Delmar Loop area near Washington University such as Blueberry Hill or Fitz's, both kid-friendly.

Yes, I meant City Museum!!!

Misty - is there a better location for us? would we be better off near Forest Park?

bachslunch - my inlaws would really enjoy the botanical garderns...thanks!

weather - our choices are end of april or end of june. i'm afraid june could be very hot, so we are going to take our chances with april.

The botanical garden is beautiful and they have a children's garden specifically for little ones.

I think you'll be fine staying downtown. It's pretty quiet in the evenings (unless there is a baseball game that weekend), and it's less than a 15 min drive away from the other attractions in Forest Park and on The Hill. It's six of one, half dozen of the other, in my opinion.

A great local custard place near The Hill is Ted Drewes. Definitely a St. Louis original.

In Branson, there is a Residence Inn that has 2 bedroom suites. http://www.marriott.com/hotels/travel/sgfbr-residence-inn-branson/
We like to stay at the Hilton Promenade at Branson Landing.
http://www3.hilton.com/en/hotels/missouri/hilton-promenade-at-branson-landing-HROBRHH/index.html.
You might consider a condo. Let us know if that is an option. There are a lot of great places to choose from both in town and at the lake.

japw - a condo is definitely and option. we would do either a 3 bedroom and share with the inlaws, or two smaller units. two smaller ones may be better for my sanity!

We've stayed at the Drury by the Arch in St. Louis. It's quite nice and in easy walking distance to the Arch. Lots to do in Branson and in St. Louis. Have fun!

I have stayed at both Thousand Hills and Branson Hills. They are both in Branson and close to everything.

http://www.thousandhills.com/
http://www.bransonhillsdevelopment.com/Lodging.html