The boys and I just spent forty five minutes trying to identify a bird song we heard early this morning, and we stumbled across this great resource in the process. After looking at and listening to all fifty birds and talking about which ones we've seen at our feeders and heard out in the woods, we concluded that our song bird is most likely a robin. Coincidentally, that's what Kelly suggested when he heard it before work this morning.
You can listen here.
A couple questions come to mind now. First, why did I assume my husband didn't know what he was talking about? Second, why didn't I know how to identify a robin's call? (I suspect the answer to the first question can be found in the second.) At any rate, I'm glad we didn't just take Kelly's (totally correct) word for it, because it was fun researching with the boys.