The lack of an ability to mark homework threads solved when they are is a discouragement to would-be homework helpers. Sometimes I browse for problems needing help but give up after looking at a few threads only to find that they are solved and no longer in need of input. There are some closed threads in here discussing this and the fact that the feature disappeared in 2008. It would be good if it could be restored. I note that many technology internet forums strongly encourage thread starters to mark threads SOLVED when they are, in order not to waste helpers' time. StackExchange uses an analogous approach of marking a question as Answered when the OP accepts an answer..