Beware, lest you overstudy - S1.E41

The opening ceremony for the new semester sets the stage for Yuu to find herself the disciple of a freshly graduated Yuuichirou Akagi who shocks class 5-1 with a test to appraise their academic prowess; if that tactic by itself is not enough to raise red flags like with Mamoru, Yuuichirou makes a house call to the homes of the students that fail the test -- a population comprising most of class 5-1. Upon having this explained to her, Natsume decides to flirt with Yuuichirou when he comes for a visit; not long after he arrives, Yuuichirou wastes no time getting right down to business with Yuu's academic performance becoming the forum for a hard sales pitch to a cram school in which the other students are not thrilled about Yuu's presence or her affinity for pacing herself. Mamoru's concern about what the cram school will end up doing to Yuu ultimately becomes the catalyst for Natsume being forced to acknowledge her fallibility when Yuu falls ill right before a crucial exam along with having demonstrated that success has far worse consequences than failure in some cases.