Hey lets put her in the closet before the teacher comes back.
ha ha yeah.
Okay class lets go outside
Why did we do that
In this part the kids were talking about how the sun doesn't come out and how they thought Margot was crazy for thinking that way. They were bullying Margot mostly in this part. In the text it says "Hey lets put her in the closet before the teacher gets back" Margot refused but there were more of them and only one of her. The kids were mean to her because she was different and she had different thoughts so they thought that treating her differently and with less respect was okay.
This part was about when the sun just came out and the teacher didn't realize Margot was gone because the children said everyone was there and there was no need and counting the students. The teacher didn't here Margot plead for help so she went on her way outside hanging out in the sun watching the kids play with each other and relaxing not knowing one of the kids is locked in a closet.
The kids realized how great the sun was and seeing what the sun made them feel made them rethink their actions and they were upset with themselves of what they did. They finally felt like they went to far with what they did because they now knew that Margot was waiting for 7 years for that to happen and they ruined it.