If you are not interested in replies, just click off the Follow Discussion button, which will be green if you are following. Is this what you mean? I am not sure if you can disable announcements on your progress, etc.
conversely, I don't want to follow every discussion I've posted to . . . but duolingo automatically signs me up to follow . . . I'd like to be able to customize that without having to go back and click "unfollow" for every one.