As a teacher, it probably doesn't surprise you that I often wander up and down the aisles of my classroom looking over the shoulders of my students to check out their answers. Oddly enough, it often surprises my students. There are those who see you coming. Some of them have not been doing their work. Danieson be damned. Asking students to self-direct their work doesn't always work when you're dealing with social beings. As you approach, a student usually clears her voice and raises it to say, "And, as I was saying." But, you know, what she was saying, she will very well not repeat. And she knows you know. So, all you can do is smile at one other.
Then, there are those good kids. They have been faithfully completing your task. They are engulfed in the middle of it. They are fully absorbed. As a teacher, you feel it your responsibility to interrupt. You must raise a point. You do so above the shoulder of a student. It is then that you first realize that the student had absolutely no idea that you have been standing there for half a minute. She receives the fright of her life. And, you feel mildly guilty after recovering from seeing her bounce a good half foot up from her seat. You have been doing your job and so has she. This is group work at its best!