Class discussions?

As i reflect on class discussions I realize they aren't discussions. This past week I was a discussion leader and had commented on several peoples post about the few topics we had and no one wrote back to me. It seems as every week it is just a one way conversation. I'm sure it wasn't just me who didn't get a response but why is it called a discussion, if we aren't discussion? I am guilty of this too. as the past weeks have just been so busy, I am happy to get on and post my discussion and let alone reply to others. Are these discussions really worth it? Maybe it would be a better idea if we took quiz es or found some other way to prove we have read the materials? Or maybe after all, I am the only one that nobody is replying too. lol