This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Wayside School
In Way-High-Up-Ball, Louis reveals a crush on Ms. Nogard, but symbolically states that "she's up [on the 30th story] while he's [on the playground]." Anyone feeling out of their league can relate to the feeling.
Allison's stay on the 19th story causes her to get so caught up in Miss Zarves' ridiculous assignments, she forgets about Mrs. Jewls and the other students. Six days later, the memories of Allison's classmates start flooding back. These memories bring her to tears as she gains a new appreciation for all their quirks, which she started feeling frustrated about immediately before Miss Zarves took her in.
Any story about animals and the song "Puff the Magic Dragon" are this to Dana.
Wendy's tragic backstory in the third book: She has a third ear that can hear everyone's thoughts. She falls in love with a man named Xavier and reveals her third ear to him. While he says he accepts it, she heard his real thoughts. And then he abandons her, resulting with Wendy's Face–Heel Turn into a secret antagonist until the end.
One does pity Xavier considering he dies alone considering what he did to Wendy.