My guess is that there’s gonna be a future chapter called Culture Festival 1, prequel to the events in this chapter, thereby making the naming of this current chapter less illogical.
I have a feeling that the previous president wasn't a genius like Ueno. That looks like just a bunch of rags stitched together.
I wonder if that black hair girl with Yamashita is Tanaka's sister, the older twin. Actually, I wonder how Yamashita got convinced to be Ueno's friend in the first place, given that she had such a poor first impression.
@Esper, I think it's less the fact that she didn't care and more the fact that she's the type of person who displays no reaction when something unexpected happens.
@Winderlies It's definitely one of them because she has the antennae hair on the back of her head, the "Tanaka tip" as Ueno put it. She looks too tall to be Mizuna though; Yomogi, the younger twin, is drawn a lot taller than the rest of the cast. We know Yamashita knows Mizuna, being in the same class, but not clearly whether or not she knew Yomogi. Their introduction chapter could be construed that Yamashita simply never realized they were twins, not that she didn't know who Yomogi was at all, since the detail that they were twins is the only thing that Yamashita reacts to.