U.S. National Chemistry Olympiad

Both steps are required. In recent seasons ACS has required a parent or guardian to register the student on the official USNCO Registration Platform at usncoreg.acs.org. The exam itself is then arranged by the regional ACS Local Section together with the school's chemistry teacher, who normally nominates which students sit the Local Section exam. A student cannot complete the whole process alone.

Yes, but the family needs to approach the local section directly. Entry is controlled by the ACS Local Section and practice varies: some accept only teacher-nominated students, while others — Orange County among them — also let students sign up via a registration form. Among the local public high schools, only Portola High School currently runs a matching Chemistry Olympiad club (the list is above on this page); students at the other schools can still compete, and it helps to have the chemistry teacher contact the section's USNCO coordinator first.

No. ACS requires entrants to be US citizens or lawful permanent residents who have attended an American school for at least one continuous year, are under 20, and are in grades 9 through 12. Students studying on a student visa are not eligible, and this is checked strictly when students advance to the National Exam and toward team selection.

Orange County falls under the OCACS local section, which has recently held its Local Section exam at Irvine Valley College in Irvine — in 2026 on the morning of February 28. That year 237 students from 37 county high schools took it and the top 13 advanced to the National Exam, which in 2026 was hosted at the University of California, Irvine. Venues can change year to year, so confirm with the section.

Not at the time we checked, and the ACS site restricts automated access, so the reliable sources are your teacher and your local section. The usual pattern is a Local Section exam on a date each section picks inside a late-February-to-mid-March window, the National Exam in April, and the study camp for the national top 20 in June. For reference, the 2026 local window ran February 27 to March 16 and the National Exam was April 18.

The Local Section exam is 60 multiple-choice questions in roughly 110 minutes, essentially accelerated AP Chemistry. The National Exam is a large step up and has three parts: Part I is 60 multiple-choice questions in 90 minutes, Part II is written free-response and problem-solving in 105 minutes, and Part III is a hands-on lab practical with two tasks in 90 minutes. National-level students must genuinely perform lab work and write up reasoning properly.

AP Chemistry is the necessary base but not sufficient. AP Chemistry courses at local public high schools cover most of the local-round multiple-choice content, but reaching the National Exam requires deeper thermodynamics, kinetics, equilibrium and organic chemistry, plus real lab practice. The most effective preparation is working systematically through the past Local and National exams ACS publishes, strictly timed, sorting mistakes by topic.

The tiers are clear. Sitting the Local Section exam shows interest but carries limited weight. Being nominated by your section for the National Exam — roughly a thousand students nationwide — is a real differentiator. Earning Honors or High Honors on the National Exam counts for more. Placing in the national top 20 and being invited to the June study camp, or making the four-member US team for the IChO, puts a student in the national elite and makes a strong academic marker for UC applications.