Glacier/Grand Teton/Yellowstone NPs - what to do?

We went on the chuckwagon horseback ride and bbq in Yellowstone and took a float trip in the Tetons. A little pricey, but if you are looking for something special/different.
In all parks, lots of beautiful short hikes/walks for all ages. Be sure to take advantage of ranger talks/walks. You will get a newspaper/activity guide at each park listing all of the programs, but if you want to plan in advance, visit nps.gov; each park has a lot of information listed and you can usually download the current park newspaper/brochure.

If you are staying on the West Glacier, pack a lunch and ride over the pass to St Mary. Lot of pull-outs for photos, especially up around Logan rest area.

Good hike is Trail of Cedars. Much of it is on a boardwalk and the trees are huge. Moss is likely thick enough to hide in with the water seeping out of the rocks. Thirty yards off the road and the noise disappears. It is amazing how quiet it is there.

While your in the Tetons, take in the Bar J Wrangler Chuckwagon dinner/show in the evenings in Wilson WY just West of Jackson, it's quite a treat. Our kids loved it way back in the 1980's and the wife & I loved it a couple of years ago once again. Call ahead for reservations, they sell out every night.

Talk with Rangers about need for bear spray if hiking and let Ranger tell kids about hiking "rules" for wild animal encounters and safety around geothermal areas. Also let kids do the Junior Ranger programs in the parks, they usually love it.

A stop at any visitor center will yield huge numbers of brochures that required many trees to produce full of things to do that will transfer funds from your account to theirs. The higher the cost, the more likely the kids will enjoy the activity.

Views based on actual experience.

If your six year old is a good hiker, the Imperial Geyser Basin is wonderful --your own private geysers! Check out this blog post and search down for Imperial:

Yellowstone and Tetons blog post -- lots of photos

In West Yellowstone there is a really cool wolf & grizzly sanctuary that the kids would love.

I really liked the hike to Avalanche Lake in Glacier. You can rent a canoe at Apgar and paddle around Lake MacDonald, and have an ice cream cone afterward.

I came across an article somewhere on "the Topo 10 things to do in Yellowstone". I can't find it now but a couple of the things were a covered wagon ride/dinner, Yellowstone lake tour, and a horseback ride. Glacier has a lot of nice hikes to lakes and waterfalls.

Get up early; pack a lunch and stay out late. Other than the thermals, wildlife and scenery you don't need any more. We do like to have lunch in all the "Lodges", but make sure you have lunch with you because you will probably get too involved to get to a lodge.