Books that made the childhood of 90s/2000s kids? For my little sisters, who are just starting to read

My little sisters (both early teens/late tweens) have finally started to enjoy reading. I’ve got them hooked with the books that were huge when I was growing up in the 2000s - Harry Potter, Percy Jackson and the Hunger Games so far. Next up they’re gonna read The Girl With All The Gifts and the Last Dragon Chronicles, but after that I’m drawing a blank.

For all those who were also a part of early Gen Z, what other books shaped your childhood/early teen years? The big ones that formed early fandom online, the ones that make you either cringe or smile at just how into them you were. Those are the ones my sisters are loving, and I wanna keep this momentum going because it’s really helping them at school.

Not looking for any of them that promote unhealthy messages, though, like the Throne of Glass series or Mortal Instruments.

Thanks!