I can see how this seemed like a good idea to him. They had learned and practiced how to write persuasive letters at school and he saw this as a logical opportunity to put his new skills to some real use. He doesn't like it when his teacher yells, so why not persuade her not to yell so much?
Logical, smart, decisive... just not very intuitive or politic.
I considered how to explain to him - AGAIN - the difference between the roles of children and adults. Why a student should be very careful about correcting a teacher or why a child should not give an adult unsolicited criticism; but I realized that no lecture is likely to clarify things for him, if it hasn't up until now, and would only serve to make him feel he had screwed up again.
So I called him back and just told him that I thought his teacher would take his letter well since it came from him. (She likes him and has said that "he cracks her up".) And that I would love to know how he persuaded her. He would only say, "Well, I gave her several good reasons."
Orangeboy isn't totally clueless. He knows me well enough to suspect that I was fishing for another chuckle at his expense and he wasn't going to give me the fodder. Oh well, just imagining his teacher reading the "friendly, persuasive letter" with all of Orangeboy's good reasons for her not to yell was enough to keep me amused for several hours.