I think if you're going to drive all the way to Deadwood or Devils Tower, you should do the Spearfish Canyon drive that same day since you're very close anyway. So, skip Jewel Cave that day and do it some other day.

The Door Trail is incredibly easy, as is Windows. I thought Notch trail was much easier than it sounded too, but there is a ladder and some dropoffs. Any of the trails can be turned into a short trail, just go partway and turn around. Most trails are pretty flat in the park.

Since you're coming from the Black Hills, enter at the Wall entrance and drive through the park west to east. You could stop at the Minuteman Missile Historical Site just off I-90 (same exit as the east entrance to Badlands). They give guided tours but you'd need a reservation to make sure you got in for that.

I think that I am going to skip Devil's Tower. I don't think that my kids would be that interested in it. I don't think that it is worth the 2 hour drive (which would be 4 hours round trip).

Should I stop at Minuteman Missile National Historic Site?

Our family with kids 10,11,and 14, did this trip last year. I think it looks like a great plan although we did not accomplish your entire itinerary.

We stayed in Sioux Falls overnight, and yes, be sure to go to Falls Park. Great for pictures and exploring. We waited about an hour for laser show to start, but it was pretty lame so we left before it was over.

Stopped at Corn Palace. Not much to see and it is odd how the town just built up around it like an old theater. It wasn't quite what we envisioned from the picture. Decided not to stop at Wall Drug, but all the signs fun along the way.

Loved the Badlands. Not quite the Grand Canyon type awe, but still amazing. Did the loop from east to west on way there.

At Mt. Rushmore, do the Presidential Loop. We had a more upscale lunch in Custer at Cedar Creek Grille--a nice break from fast food stops.

Loved the tour deep into Jewel Cave! And the Mammouth Site was worth it as well. Saw free roaming buffalo along the way.

One of the kids favorite days was spent at Rushmore Waterslide Park. Not at all like a Disney waterpark,but the small size was nice. We could sit at the base of the slides and watch the kids from most angles go up and down the various slides. Plus, adults could get in at a discounted rate if they did not use the slides. It was a nice break from all the touring.

Have fun!

Take the short hike around Sylvan Lake and you could drive Needles Highway the same day as it is right at the lake as well. I would vote for Wall Drug over the Corn Palace. The Trial of Jack McCall in Deadwood is a fun reenactment for kids and adults. Try to plan the cave tours during the hottest times of the day. The trail rides at Blue Bell are great fun. Spearfish canyon is beautiful. Mammoth site is well worth the trip to Hot Springs. The Badlands are amazing. You have picked some great activities, enjoy!

I'm doing a similar trip in 2014(not with small children). I am debating between staying in Custer(like the OP mentinos-some place like Holiday Inn Express, etc) or in Custer State Park at one of the lodges. Any opinions on that?

I looked at the reviews of the cabins at Blue Bell Lodge. It looks like some of the units are new, but some of them are pretty old. I like the Custer location since it appears to be a very central location. It looks like a lot of the good vacation rentals are booked for this summer already. If you are planning on staying in one place for 4 or more nights, you might want to look at a vacation rental at http://www.vrbo.com.

Staying in the hills is more peaceful than staying in one of the towns. Custer State Park is one of the most beautiful places anywhere so if you can get into one of the lodges I would do it.

I ended up booking a Camping Cabin at the Blue Bell area of Custer State Park. For the end of the trip, I booked a Blue Bell Lodge Sleeping Cabin. Here is the link for the virtual tours of the Blue Bell Lodge cabins: http://www.custerresorts.com/blue-bell-lodge/virtual-tour/. They just started taking reservations 3 weeks ago. These cabins go fast.

With kids that age, do one cave not both they are very similar, the Mammoth site is great, Custer State Park has lots of wild life, Needles Highway is a great drive and Sylvan Lake a good walk. As I mentioned in response to your other post, Wall is a tiny odd tourist trap place, not sure kids will get anything out of it.

Wall is a good stop for kids. It's a chance to get out of the car on an otherwise long drive from Sioux Falls to Custer. The Corn Palace is a similar quick diversion.

Your itinerary is ambitious. You have a lot packed into each day. We did this trip with our children a couple of years ago. It was difficult to fit in all of the area's attractions in a week. With summer tourist traffic and crowds, it took us longer to get to and tour each place than I had anticipated.

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Spirobulldog, there are several acceptable places in Custer, such as Best Western, Holiday Inn etc, if you can stay in the park go for it.Some of the decision will depend on if it is a road trip, moving every other day, or staying in one place and traveling around in the vicinity
Shorty your itinerary is ambitious and almost everything will take more time than you anticipate. Also Chicago to Sioux Falls is a long drive for one day, I can hear the "are we there yet"

Here is my revisted trip plan.

Day 1 (6/6, Thurs.): Drive from Chicago to Sioux Falls. 9 hour driving day.
Lodging: Brimark Inn (Sioux Falls, SD)

Day 2 (6/7, Fri.): 4 hour drive to Circle View Ranch. Visit Minuteman Missile and go down the street to The Ranch Store to feed the Prairie Dogs. Go to the Badlands visitor center and get a Junior Ranger workbook. Do a trail(e.g. Door Trail, Cliff Shelf Nature Trail, Fossil Exhibit Trail) and possibly do a ranger led activity. Drive around the park at dusk.
Lodging: Circle View Ranch (Badlands interior area)

Day 3 (6/8, Sat.): Drive around Badlands early. Drive Sage Creek Rim Road to see Prairie Dog Town? Stop by Fish Hatchery and Cosmos Mystery Area in Rapid City. Get Jr. Naturalist information at the visitor center. Eat dinner at Sage Creek Grille in Custer.
Lodging: Comfort Inn & Suites (Custer, SD)

Day 4 (Sun.): Drive the Custer State Park Wildlife Loop, Horseback ride at Blue Bell Stables (2 hours), visit Sylvan Lake area and eat at the Sylvan Lake Lodge, do some short hikes. Eat dinner at State GameLodge
Lodging: Blue Bell Camping Cabin (Custer State Park)

Day 5: (Mon.): Visit Wind Cave at 8 for tickets to the Natural Entrance Cave Tour, visit Mammoth Site at Hot Springs. Attend the Blue Bell Lodge Chuckwagon Dinner.
Lodging: Blue Bell Camping Cabin (Custer State Park)

Day 6: (Tues.): Drive the Spearfish Canyon Scenic Byway and walk 10-15 min. to the Spearfish Falls. Try the Alpine slide if there is time. Go to Mt. Rushmore, see the museum, do the Presidential Trail.
Lodging: Blue Bell Camping Cabin (Custer State Park)

Day 6: (Wed.): Go to Hill City and pan for gold at Wade's Gold Mill. Eat at Alpine Inn for lunch. Drive the Needles Highway and. Visit Crazy Horse Monument.
Lodging: Blue Bell Sleeping Cabin (Custer State Park)

Day 7: (Thurs.): Visit Jewel Cave (take scenic tour). Do some ranger led activities at Custer Park? Lodging: Blue Bell Sleeping Cabin (Custer State Park)

Day 8: (Fri.): Stop by Corona Village (Mitchell, SD) for lunch and Corn Palace (Mitchell, SD). Drive to Fairmont, MN. (7 ½ hr. driving day)
Lodging: Hampton Inn (Fairmont, SD)

Day 10: (Sun.): Drive back to Chicago (7 hours)

Oops -- I made a mistake above. The trip should be a total of 9 days with the trip ending on a Sat.

Has anyone been to the Badlands Petrified Gardens? Is it worth visiting?

I was thinking of going rockhounding with the kids, but am now thinking that it might be better to buy rocks at a store instead of venturing into some area which may have rattlesnakes (e.g. Buffalo Gap National Grassland).