From the NACLO website:

"The North American Computational Linguistics Olympiad is a contest in which high-school students solve linguistic puzzles. In solving these puzzles, students learn about the diversity and consistency of language, while exercising logic skills. No prior knowledge of linguistics or second languages is necessary. Professionals in linguistics, computational linguistics and language technologies use dozens of languages to create engaging problems that represent cutting edge issues in their fields. The competition has attracted top students to study and work in those same fields. It is truly an opportunity for young people to experience a taste of natural-language processing in the 21st century."

For more information, see http://nacloweb.org/