Having the right tools to prepare for Local, National and International Olympiad Exams is the key to success at each level. To prepare for exams, explore our resources below to:
All students must be registered by their parents/guardians to participate in the 2026 USNCO competition.
Links to annotated files are included next to the corresponding exam below. Detailed solutions are provided directly in the files for National Exam Parts 2 and 3.
Detailed solutions are provided directly in the files for National Exam Parts 2 and 3.
Solutions are kindly annotated by our volunteers, view all acknowledgments. Sign up as a volunteer to annotate past exams.
The USNCO Teacher Training Course is an online, self-paced course in the ACS Learning Center that offers supplementary knowledge often not covered by a typical high school chemistry curriculum, useful when preparing for the U.S. National Chemistry Olympiad Exams. The course materials are primarily designed to support high school chemistry teachers but they can be also used by the students preparing for the competition.
The course has 10 units related to the topics covered by the USNCO exam. Each unit is designed to be completed in about 40 minutes to 1 hour. After completing each unit of the course, you can receive a certificate for that unit.
USNCO Coaching
The USNCO Coaching program helps high school students improve their chemistry skills and become more competitive for the U.S. National Chemistry Olympiad. Students receive extra help during 2-hour sessions for small groups, led by coaches from across the U.S. Coaching sessions are organized over Zoom and coordinated by the American Chemical Society.
Coaching sessions will last for two hours on Fridays every other week in January and February of each year. At each session 30 minute tutorials are be followed by 1 hour and 30 minutes of small group work in breakout room. Student application deadline is December 15, 2025.
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