When I was a (supposedly) precocious preteen, I was captivated by Dandelion Wine by Ray Bradbury. The style of it was like the modern idea of mindfulness, with a character intrigued by a favourite brand of pencil, for example, and the physicality of the rugs being beaten clean by his grandmother.
I’ve reread it several times since my childhood and still hold that it’s an excellent read for the younger generations. It has dark moments but they are childlike and gentle in their handling and so not really frightening or disturbing.
My Antonia is a great suggestion. Speaking of L'Engle, The Moon by Night is good too.
Kids this age are facing--every weekday--the possibility of being slaughtered in their classrooms, and are often startled out of their seats by drills in which they cram themselves into closets to escape bullets.
Consider buying them nonfiction as well as fiction. History, politics, both adults and young adults of all races and genders who have faced down tragedies and changed their eras for the better.
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My middle schooler prefers nonfiction. A few that have worked in our house (despite somewhat grim topics, they all end at least semi-well): Chasing Lincoln's Killer and the Young Adult versions of Hidden Figures and Unbroken,
Empire of the Sun by J. G. Ballard for the older readers, and A Long Trip to Teatime by Anthony Burgess for the middle school readers.
Also, a few of them may enjoy Sue Townsend's droll and hilarious books. "The secret diary of Adrian Mole, aged 13 3/4" and "The growing pains of Adrian Mole."
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Point them towards Zilpha Keatley Snyder and William Sleator if they are inclined to stories with an element of the unusual. Also, Kelly Link's amazing short stories, and Neil Gaiman (of course.)
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