Panel 1: We start things off with a shot of a male bird making a mating display.
Panel 2: We zoom out to see Dawn pointing at what she's seeing and saying "WOW!" to gain Liz's attention.
Panel 3: We start things off for real when Dawn tells Liz to look at the bird because she thinks that it's acting really stupidly.
Panel 4: Liz tells her that her mom says that in Springtime, male birds do such things to attract females.
Panel 5: She goes on to say that Elly says that if the female bird is impressed, she becomes its mate.
Panel 6: She then unintentionally repeats back some passive-aggressive bitchery at John's expense when she says that other animals do that sort of thing too.
Panel 7: When Dawn asks "Really?", Liz says "Yeah" because for once, Elly isn't talking about a sort of fantasy mechanistic cartoon cosmology that has angels paint frost on windows.
Panel 8: As we see Christopher on his bike doing something stupid in order to gain Liz's attention, we laugh because he's doing so in vain because Liz says that she hasn't noticed any.
Summary: Nine Year Old Liz's inability to really notice when a boy is trying to signal his interest in her is a survival of little kid behavior and is almost believable (if somewhat gender inappropriate); the Liz who made a concerted effort to not notice Anthony's interest in her was, as History will show, too damned filled with self-pity to want to notice. She wanted to wallow in self-pity about her looks and the existence of a boy who had weird rescue fantasies about her is not something she wanted to have in her life because it would deprive her of the joy of being needlessly miserable.