I think some of the questions that need to be asked first is how old is the child, male or female. At to young of an age, it is difficult for them to handle to much weight, or to long of a rod. I have a daughter that uses a 4 weight 7'6" rod and she loves that one, but when I hand her my 5 weight 9' rod, it just wears her down to fast and she complains. If you are just going after the sun fish to start, and you want them to really enjoy the fishing. I would start them out on something they can handle. Deffinitely go to a good Fly shop and ask to have them try a few of the rods. See which ones they can handle. Then make the decision! But having something that fits, will certainly keep them wanting more!