[kaisen]

As others have suggested, the large national parks (Yellowstone, Yosemite, etc) will be very memorable for your 8 year old, a little less so your 5 year old, and a giant pain with your 2 year old.... I'd wait a couple years for one of those trips.

Renting a home/cabin on some beach or lake is probably the easiest way to have a nearby home-base when the youngest (or parents) need rest and the others want to play. A good resort can provide that as well.

Another option is to rent a motorhome or travel trailer (even pop-up) to visit some surrounding attractions in an area (i.e. Black Hills, SD) and use the RV as home-base.

Fly in to Sacremento or Reno, pick up a Class C RV rental there, drive to Yosemite, the redwood forests, etc?

Or rent one simply to stay in a campground for the week and "rough it". Many state and national campgrounds are breathtaking and have good facilities (flush toilets, hot showers, well-lit, safe) for family camping.

I think at 5 and 8 they would love camping, making fires, eating on picnic tables, setting up camp, etc.

Another option is the Wisconsin Dells area near Baraboo, WI. Lots of water parks and resort-style accomodations with their own indoor and outdoor water parks. Ride the Ducks (WWII amphibious). Amusement parks. We've stayed at the Wilderness and the Kalahari, but there are several large resorts. The only downside is proximity to an international airport....you're going to drive from Madison, Minneapolis, or Milwaukee.

If that sounds appealing, there is also a fantastic campground/resort at Jellystone in Warrens, WI that is within driving distance of the Dells. Your family would love Jellystone Warrens, like camping but with more kid-directed facilities and activities.....a blend between camping at a state park and staying at Disneyland. They rent air conditioned cabins or park-model trailers.

There are so many lake resorts in Minnesota, Wisconsin, Michigan.....any of them could be a wonderful, natural vacation. If you'd like specific resort advice, let us know here. I'm sure other Pelicans have their favorites as well.

Look into Door County, WI? The Adirondacks? The Boundary Waters?

My daughters are 2 and 3. They love to camp. They love the water, beach or pools. My advice is given based on what my own daughters could enjoy, and what I could do without pulling out all my hair. However, my girls are great in the car so long drives aren't a big constraint.