International Linguistics Challenge (ILC)
International competition with multiple rounds of linguistics/logic problems; closer in style to math/science Olympiads but focused on language.
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7EDU Global Academy NACLO Site (Bay Area)
Only public Bay Area high‑school NACLO site; good option if your school doesn't host the competition.
BYU NACLO Site
Brigham Young University NACLO competition site; host information and registration for students in Utah and surrounding areas.
North American Computational Linguistics Open Competition (NACLO)
Flagship North American contest where students solve linguistics and computational linguistics puzzles; top scorers can make national teams for IOL.
Online Olympiad in Linguistics (OnLing)
Fully online international linguistics contest with a dedicated school‑age division; problems look like IOL/NACLO style puzzles.
University of Washington NACLO Site
Local NACLO competition site at University of Washington; provides on-site support for students in the Pacific Northwest region.
National Japan Bowl (Japan-America Society of Washington DC)
Quiz‑bowl style competition on Japanese language, culture, history, and society for high‑school teams; top teams invited to national finals.