Carnegie Mellon University


The North American Computational Linguistics Open is coming to Carnegie Mellon University on January 25, 2024! 

What is NACLO?

The North American Computational Linguistics Open is a contest for U.S. and Canadian high-school students, who test their minds each year against fun and tricky puzzles in language, linguistics, and language technologies. No prior knowledge of linguistics, languages, technology, or computers is required: even the hardest puzzles require only your logical ability, patient work, and willingness to think around corners. For more about NACLO and to try some sample puzzles, visit the NACLO website at

What's the schedule?

Open Round, January 25, 2024:

  • Check-in: 9:00 to 9:30 A.M.
  • Students take their seats: 9:30 to 9:40 A.M.
  • Welcome and review of rules: 9:40 to 10:00 A.M.
  • Exam period: 10:00 A.M to 1:00 P.M.

Invitational Round, March 14, 2024

The NACLO Open Round exam will take place in the Gates Hillman Center (GHC) at CMU. (See these directions for information about getting to campus and parking.) You can enter the GHC either through the Gates Center for Computer Science or through the Hillman Center for Future Generation Technologies; these buildings connect and you can enter through either one.

When you enter Gates Hillman from the Forbes Avenue entrance, look for the NACLO check-in table just inside the entrance. Check-in will take place in the 4th floor Hillman lobby near the Rashid Auditorium and room GHC 4405.

Who do I contact for more information?

Dr. Lori Levin, NACLO Co-chair and Research Professor
Language Technologies Institute
Carnegie Mellon University
Tel.: 412-268-7517

Contact John for information about contest day procedures and other administrative questions. Contact Lori if you have questions about NACLO in general and for school visits and trainings.

Who's eligible to participate?

Any high school or middle school student is invited to participate in the Open Round.

The top-performing students in the Open Round will be invited to participate in the Invitational Round on March 14th.

What happens in cases of school delays and closings?

Because NACLO is a nationwide exam, we must adhere to the test schedule and test with the Eastern time zone on January 25th. Therefore, in the event of any school closings or delays, NACLO will proceed as scheduled. Unfortunately, we will not be able to offer a make-up day for those students who were unable to make it to Carnegie Mellon in time for the exam.


NACLO and NACLO@CMU are made possible by generous support from both institutions and individuals. Even small donations make a big difference, so take a look at our donation page to see how you can contribute.