Best Books for High School+

Why "High School+" instead of individual grades?

Above grade 8, reading level becomes less meaningful as a standalone measure. A book like The Martian by Andy Weir reads at roughly a 5th-grade level but is clearly written for adults. That's because Lexile and reading-level scores measure text complexity (sentence length, vocabulary) — not thematic maturity or intended audience. Since relatively few books score above a 9th-grade reading level, we group them here rather than splitting across sparse individual grades. To find books appropriate for older readers regardless of reading level, look for the UG (Upper Grades) interest level on each book's page.