This article contains spoilers for the Classroom of the Elite Light Novel and Anime. Sae Chabashira may be a teacher, but only in the very broad sense of the word, as the title of Offical Observer is more fitting for this sensei. While the whole educational system in Classroom of the Elite can be described as particularly hands-off, Chabashira takes this mentality to a whole new level and remains as uninvolved in the affairs of her class as possible.
She rarely offers advice or encouraging words of wisdom, instead giving the distinct impression of complete disinterest in Class 1-D's success. However, Chabashira evidently has an old rivalry with Chie Hoshinomiya, and suddenly seems particularly invested in Ayanokoji's future, but why the change of heart?
The Teachers' Rivalry
Miss Chabashira is a product of the very same school she now teaches at, with her childhood friend, Chie Hoshinomiya, following the same path. The young Sae was unfortunate enough to also be placed in Class 1-D during her school years and was therefore forced to prove herself, assumedly without much success. She does not appear to enjoy reflecting on the past, which she states is full of regrets, reaffirming the suspicion that Chabashira did not reach Class A herself before graduating.
Besides her little one-on-one chats with Ayanokoji, the only other time that Chabashira reveals her goal of Class 1-D's ascension is when things begin to get competitive between the teachers. She gets particularly riled up when comparing her class's potential with Chie Hoshinomiya, the homeroom teacher of Class B, as both ladies have their sights set on the Class A spot. However, Sae seems to have more faith in her student's skills than the alcohol enthusiast Chie does, indicating that they may be in agreement about Ayanokoji possessing superior capabilities to Honami Ichinose.
The Code of Conduct- Teachers' Edition
What most students may not be aware of is the fact that their teachers are expected to compete with one another, and that their class's status directly reflects on their own success. It seems that Chabashira goes to great lengths to appear blase and disinterested in the whole matter, implying that this is just a job and nothing more; and only the minimum effort can be expected from her. But Miss Chabashira's juvenile need to be acknowledged and accepted at Koudo Ikusei Senior High has evidently followed her into adulthood, although she tries very hard to hide her intentions. The sting of failure is not as severe if one's ambitions are unknown.
The staff at Koudo Ikusei Senior High are also specifically encouraged to not intervene in any of the student's problems, and generally speaking, Chabashira follows those rules to a T. She was willing to allow Ken Sudo's unjust expulsion via Class C's instigation, and was also willing to boot him from the school herself because he was just one point short in a test. She turns a blind eye to Karuizawa's bullying and outright refuses to prevent Ryuuen from taking things further in the Light Novel when the severity of the bullying intensified.
A Missed Opportunity
The first time Miss Chabashira shows her faith in Class 1-D is after Ken Sudo is nearly expelled due to his test scores, which she uses as an opportunity to uncharacteristically dish out some advice. After watching her students consistently struggle, berating them without giving any assistance, Chabashira eventually informs the group of their potential to advance to Class A status, offering them a glimmer of hope for the future. She has likely seen very few selfless acts in all her years at this cut-throat school, and the fact that Ayanokoji and Horikita sacrificed their private points to help such an unlikeable classmate must have sparked Chabashira's aspirations, prompting her to spur her students toward greatness.
So far, the only person who seems capable of persuading Chabashira to get involved in the affairs of her students is Ayanokoji, and he likely only has any sway because he is the ultimate trump card. Ayanokoji may have many of his classmates fooled, but Chabashira is fully aware of his advanced intellect and has some useful insights into his mysterious past. Blackmailing somebody is undeniably an immoral act, but Chabashira goes to this extreme in an attempt to force Ayanokoji's hand in assisting with Class 1-D's success, knowing full well they would get nowhere without him (in her opinion, anyways.)
In the Classroom of the Elite Light Novel, however, Chabashira's cover is blown in Volume 7 when it becomes apparent that she had not received direct instructions from Ayanokoji's father to get him expelled. In fact, the young man was placed among her second-rate students so that he could remain under the radar, with the intention of completing his high school career without attracting too much attention. Chabashira, however, could not resist the temptation of pursuing her dreams and goes out of her way to manipulate Ayanokoji into helping her, essentially backing herself into a corner in the process.
She was given the instruction to protect Ayanokoji and attempt to inspire some kind of sentimental attachment to the school, so Chabashira assumed she could kill two birds with one stone by aligning their goals and aiming Ayanokoji's attention toward the Class A title. However, she becomes so focused on the boy's potential and how to unlock it, that she overlooks all the other diamonds in the rough. She completely disregards exemplary students such as Horikita, seeing her only as a tool with which to manipulate her target, but otherwise insignificant. If Chabashira had invested as much passion into her other students as she has (very subtly) done with Ayanokoji, who knows how successful Class 1-D would be today?
Season 2 of Classroom of the Elite is currently streaming on Crunchyroll.