Poets & Writers – Contests Database (Teen‑Accessible)
While not just for teens, Poets & Writers' contest database includes some competitions open to high schoolers (e.g., youth categories, general contests that accept under‑18 with permission).
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Bennington Young Writers Awards
Prestigious competition from Bennington College with categories in poetry, fiction, and nonfiction; winners/finalists often receive big scholarships if they attend Bennington.
International High School Writing Contest
Global analytical and creative writing competition with categories like short story, flash fiction, poetry, critical essay, and dramatic script; no entry fees.
NewPages Young Writers Guide to Contests
Curates "legit" contests for youth; includes many teen‑specific poetry and prose competitions.
One Teen Story Contest
Short story contest for teen writers; winner is published in One Teen Story and receives a cash prize.
Harvard Crimson Global Essay Competition (HCGEC)
International essay contest organized with The Harvard Crimson, with multiple prompts and a focus on critical/creative thinking and writing.
John Estey Student Writing Competition (American Writers Museum)
Essay/narrative competition on topics related to American writers, literature, or culture, run by the American Writers Museum.