"Sophia is smart" She gets up and shows off her panties with a silly smile in class. And she would probably stand for the entire lesson until the student noticed her. the class does not hear it at all, is deaf and blind. It would be more rational for L&P to add a dialogue with the environment where whispers and murmurs can be heard in the classroom that the students are seeing something after all. I may be wrong, but nowhere does she say in the dialogues that rumors are circulating at school about strange lessons from Sophia.
Sophia is smart" Stupid and illogical when Sophia takes the calls of Aiden and Andre. No one else in the classroom has a phone. Everyone has it and everyone can record Sophia in a moment.
You might know that I am a longtime critic of L&P, but here I think it is different school systems experienced. L&P is porting over his experience of German school to a school in a fictional US. German school is at later stages a three-ways- approach (don´t get me started on this stupid one way Gesamtschule crap) with Hauptschule, Realschule and Gymnasium. The Gymnasium branch is the upper level geared towards University and white collar work, but not a few still become Apprentices later.
While time has gone by since my Abitur, back when I was in Gymnasium, a clothing "gaff" like this would have been reacted to quite similar. Part "Stealthy Watching", part "we overlook this until someone hints what is going on" (Teachers were persons of respect back then) and someone like the class speaker politely hinting that something is amiss. Case solved, might have a bit of gossip later, but not much else, esp. if the teacher in question was popular.
As I wrote in another post, the differences between school systems are large. We have no dress code for teachers beyond presentable or what I know from US schools, pupils calling teachers sometimes with their given names, is not normal here. In Germany teachers are called "Herr/Frau xyz" and are "gesiezt"(polite form you, no equivalent in modern English)
Second, especially in the higher level schools there is a general "Cell phone is off and in the bag" rule during class in German schools, only if there is a significant reason a cell phone can stay on, but still out of way.