How long are you in port and what time is your Dog sledding??? Your 5 year old probably won't be interesed in any of them and only a possible interest of the 9 year old. Do they LOVE trains?? My kids did and the White Pass RR was a high point, but I have also seen a lot of bored kids. I really like Haines, and Yeshua runs an excellent tour but it is not probably of interest to kids. I can't recommend the 4x4 trips, they are not enviromentally sound for Alaska in my opinion. You may be overlooking other options- any chance of a scenic hike? Lower Dewey Lake would be doable with good views and an adventure for the kids, as well as some sound excercise?? The National Park service has plenty of free stuff, museum, movie, ranger talks, ranger walking tours. Another option if your 5 year old has some stamina- is the level 1 1/2 mile (one way) back to the Gold Rush Cementery. You could walk through Skagway, pass the train sheds, etc.