Tuck Everlasting is one of my favorite books that I read in school. Ten-year-old Winnie Foster is enchanted when she meets the Tuck family, who are unlike anyone she's ever met. She soon discovers their secret: they cannot die. After drinking from a magic spring many years before, they found that they never aged. Now they move through life, trying to remain inconspicuous and find purpose in lives that never end, and Winnie must decide if she wants to follow the same path. This is a classic middle grade book that prompts discussions about family, choices, and mortality. It's one of the first books that come to mind when I think of excellent middle grade writing: artistic but straightforward, and above all, respectful of the reader's abilities to wrestle with difficult questions.