This is the first cruise that we have participated in the FE, but from what I understand there are a few different ways to do it. WE are planning on finding something that is from Idaho, planning on something for each of the participants of the FE exchange. (Is everyone participating? what was it... 91 adults and 70 something kids? YIKES AND EEEKS!).
Some people are using a treasure chest that can be made from a kit at Michael's for their FE, we have made our own (no I am NOT posting a photo, you will have to wait and see it for yourself!). Ours has a pocket with each persons name on it, I let the kids create their own.
There is a metal fish outside of each stateroom that you can hang it from, thus the name "fish extender"! I think it is best to personalize it some way, so that they don't disappear like some people have said happened to them! I don't think anyone else with have a son named Kaj, so we should be ok! LOL!