We are travelling mid july, with a boy age 12 and girl age 9. Neither is into strenuous hiking. We have an itinerary of Bear tooth Highway to Cooke city for 3 nights, Lake Yellowstone hotel 2 nights and Jackson Lake Lodge 2 nights- What activities would be big winners with the kids? We will have an SUV but fishing and big hikes are not on their list

http://www.nps.gov/yell/home.htm

This will get you started with things to do in the park. Make sure you have a good size cooler and stock up some of your favorite items you like to munch on and drink. The stores in the park are expensive and what you will find is limited, you also will be spending a lot of time driving around and thats when this planning will be appreciated. Since you are planning on the BearTooth this may be of some interest.
http://www.mdt.mt.gov/travinfo/beartooth/

You can see a lot of the park by taking short walks. The park is laid out like a figure 8. Drive the upper loop while in Cooke City and the lower loop while at Lake Yellowstone.

It's just a short walk to see the Tower Falls, Grand Canyon of the Yellowstone, Mammoth Hot Springs you can walk as much or little as you want. The geyser areas are not long hikes, but several short walks. The longest will probably be around Old Faithful. My guess will be that they will want to do these walks because this is such a beautiful area and so many interesting things to see and do. Also don't miss the Mud Volcano area and West Thumb. Try and be in Hayden valley yearly in the morning or late evening to see wildlife.

Utahtea

There is so much to do! Float trip on the Snake River in Tetons, Chuckwagon Dinners in Jackson. You can rent canoes or boats at Coutler Bay or hike out to Swan Lake and see the nesting trumpter swans (and moose too). Horseback riding in both parks, chuckwagon dinners in Yellowstone too. Ranger lead geyser walks are interesting too. Boat ride on Yellowstone Lake.

Be sure to carry binoculars with you. On the top of many of the "hoodoos" the length of the Canyon of the Yellowstone you will find osprey nests which might still have young about ready to leave the nest if they haven't already. There is another large nest at the last pullout before you get to the parking area for Tower Falls. The pullout on the left as you are coming from Tower Jct is directly across the road from a hugh wall of columnar lava. There is a nest on top of the middle hoodoo on your side of the river below you. There is a great walk along the top of the wall of lava you are looking at on the other side of the river. To get to the trailhead go back to Tower Jct take a right like you are going to Lamar Valley. Will cross the river and a short distance after that will come to a picnic area on the right. Will find the trailhead to the left of the restrooms. Have found the Tower Falls area to be good for see black bear.
Be sure to visit Lamar Valley early and late in the day for a chance to see the wolves. Will usually see a number of cars parked along side the road. Will have to climb up the hill of moraine to get a better view. Folks set up spotting scopes for others to use.
Walk around the geyser basin at night.
In the Tetons either take the boat across Jenny Lake or better yet walk the easy 2 miles around it and then up to Hidden Falls. Or walk around String Lake. The Oxbow is a good spot for wildlife at sunrise & sunset. Great mt views with possibility of moose is at end of Schwabacher Rd.

Great information, Photodog. Thanks for sharing!