Lids can get everywhere and get lost easily (especially things like sippy cup lids). Solution? Store lids directly with their container, on it if possible. We keep all our plasticware lids inside a large plastic tub. We keep our CorningWare lids in or on the dishes. We keep sippy cup valves in the cup with the lid on it. Storing the lid with its correct container will save you time and hassle trying to match them up when you need them.