The way we're meant to read it is probably just "she wants an excuse to keep coming to the library" but in light of this chapter also causing both of them to realize just how bad they had it for each other I do wonder if another reason why Yamada decided to start doing her homework and study in the library instead of just pig out on snacks and flirt with Ichikawa is because her attitude towards school shifted from "I don't need to do well in school for my intended career path so I'll just coast and have fun" to "I need to get my shit together and do well enough that I can go to the same high school as Ichikawa."
I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded I folded.