Well, even for someone as opinionated as I am, it is hard to answer such a question. But, I do think “good” and “bad” are “bad” labels for children’s behavior.
For one thing, much of what children do is experimental; they are small physical and social scientists. “What will happen if I drop this biscuit on the floor?” “What will happen if I toss this block at my Mom’s head?” “What will happen if I pull this person’s hair?” Our main job, is, always, to teach, with words and with actions. “I can’t let you do that.” (Get them out of the chair, away from the blocks, away from the hair, and let them have their feelings about that.)
For another, you know that you often do “bad” things for “good” reasons, and vice versa, like the video of the little boy comforting his little sister after he slapped her in the face. It is hard to know the thinking behind something. Is it good to get an ice cube for Gramma’s drink? Yes. Is it bad to climb up the refrigerator shelves with your muddy boots and to leave the refrigerator open so that the dog can eat tonight’s dinner? Yes. Is it bad to take your sister’s doll? Yes. Does it make it okay to hand her a a spoon to play with instead? Maybe, let’s see.
This also puts all morality into our heads, and not in theirs. It reminds me of the scene in Harry Potter when Mrs. Weasley says: “RON! I’d better not catch you doing that again!” And he replies: “You won’t (catch me, that is.)” We want children to have their own experience of morality. To me, we learn this when others tell us how what we do effects them. This is why “I messages” are important in communication. “I am frustrated that I washed your laundry and you let the dog sleep on it. Now it is dirty again. This time you will help me wash it.” It may or may not be “good” or “bad” to make a bed for the dog, but it effects you. Children are the best teachers of each other in this way. It is almost completely ineffective for us to tell children what is hurtful or harmful to other children, but very effective for children to tell each other. Although it takes a lot of time.
This also allows us to stay on the child’s side :” I see that you are sad that he said that he didn’t want to play with you after you took the ball. Why do you think that is? What could you do about it? You can try again another day.”