Just had a great overnight with my two youngest kids. It was a short out and back, about 2.5 miles each day. My son is 9 and my daughter is 11. It was the second time I have taken my son and the first trip for my daughter. The night was cold at 35 degrees but we had warm enough bags and an extra blanket.
I don't have much experience backpacking myself so for me the key is to keep it simple. We went close to home, just a two hour drive to the Manistee National Forest. A short hike, only about 2.5 or 3 miles each day. The terrain was easy but there was natural beauty to keep them interested. We walked past three lakes and camped near a lake. We saw a pair of Bald Eagles on the hike out. Most importantly both kids felt like they accomplished something.
Loc: Gateway to Columbia Gorge
Hooray for you and your kids! Anyone who is willing to take his/her kids out is contributing a considerable amount not only to the future of backpacking but to the future of wilderness and keeping kids in touch with the natural world!
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey