DS was also attached to things emotionally and not ready to let things go. We had a neighbor with lots of boys who would give DS hand-me-downs. Many of these became favorite items. So I pointed out how much he enjoyed things that other people gave to him when they outgrew it. One can donate to a specific child or to an organization who can find children who need those things now. Fortunately, it was around the time Rudolph was showing and he was able to "see" how unhappy the toys were at the Island of Misfits. So it resonated with him.
Some things are very special, so we keep those. Others, we find another child to "donate" to and we accept "donations" into our home as well. This way, instead of throwing something away and devaluing it, the concept is more about sharing and keeping the value of the item intact. Hope that makes sense.
Actually, we also already have a very active cycling of hand-me-downs (and even hand-me-ups, whereby we receive items about 3 sizes too big from one friend and give them to another friend whose son is 2 sizes bigger than DS6 so that he can wear it until it is passed back to us) going on in our house. And he doesn't seem to mind when items are outgrown and given to someone who will use it. We also have a box for keepsakes.
The real problem is with stuff that truly is garbage - the stuff like dried out markers, stickers full of dirt, and shoes with holes. At some point, items truly are no longer useful. And ultimately, I also want to teach the boys that it's the people and experiences that matter, not the stuff. I'm ok with the fact that it'll take a while, but it can sometimes be quite exasperating. Like the time when I had to go fish into the garbage can to retrieve the dried up marker...
