Forgiveness

I'm wondering why students who didn't do assignment should be punished. Thought I'm not one of them, I think there must be some reason for them. Why don't teachers put themselves into students' shoes? What do students learn from "homework" at all?
We have experienced the same states at our English Listening classes. Note, I'm not saying something bad about the teachers below. Not only did Miss Lin who was our instructor last semester but Miss Liu who is our English Listening instructor this semester, as well made us feel embarrassed when they asked students how to punish their classmates who didn't do assignment. How embarrassed we were. Could any student jump up and tell what the punishment was or give a reason to keep his/her classmate from being punished? Usually, we dare not.
Education is very important to everyone. However, it shouldn't be like that. I admire the students who admitted that they didn't do homework to teachers without giving hackneyed reasons such as “I was sick.” and “I forgot!” because they were frank and brave to their faults. Being honest is more important than giving any reason to argue with teachers.
Why should persons be to blame or be punished without doing something that was asked to do? Well, maybe I can't express clearly what I wan to say, therefore, I give two examples below:

If you were a teenager, what would you prefer to when you happened two the situation?
Situation 1:
Papa: What time is it now? Shouldn't you come home early? You are grounded!
Situation 2:
Papa: How afraid I am to lose you in the dark. I've been waited for you and kept worrying about you. I'm happy that you came home without being hurt at midnight.
I bet you tell the differences between the two. I guess students will be moved and drop their bad habits when heard "There must be something more important than your assignment or you won't do your lessons. What's bothering you? Tell me about it! Though I can't do homework for you, I want you to do it without being annoyed." Students learn by teaching. However teaching shouldn't come with orders and without reasons. It might be tragic if the education system in Taiwan teaches students to anticipate what the teacher wants to hear and to feed it back to him/her. "Forgiveness" is a big lesson for everyone. Could people be taught "Forgiveness?"

May I have someone to tell me "Where did you learn forgiveness from?"