Members of the 2019 USNCO team (L-R): Edward Jin (Arnold O. Beckman High School, Irvine, CA); Anton Ni (University High School, Irvine, CA; Yajvan Ravan (Churchill High School, Livonia, MI); and Albert Liu (North Hollywood High School, CA). ©Melissa Barranger-Mathys

Involvement with the American Chemical Society (ACS) U.S. National Chemistry Olympiad (USNCO) program is a rich and rewarding experience that benefits top students and their teachers in local sections. 

This article describes my own involvement with the USNCO program and offers details about the program and its exam. It also includes some reflection on how others can become involved with the program. 

Promoting excellence in chemistry

The USNCO program is a national competition for high school students, whose purpose is to stimulate young people to achieve excellence in chemistry. The widely recognized competition serves as a qualifying exam that leads ultimately to the International Chemistry Olympiad. By working to increase participation throughout an ACS local section, schools (and their students and teachers) can earn acknowledgement for their achievements in the USNCO.

My involvement with USNCO and ACS dates back to the late 1980s, when Dr. Wallace Gleekman, my former chemistry teacher at Brookline HS and a James B. Conant Award winner, suggested I take over his role as writer and administrator of our local Chemistry Olympiad section exam. More than 30 years later, my involvement with our local section on behalf of our top students and their teachers continues to be professionally rewarding and important. Seeing and adopting national trends at the secondary chemical education level (such as microscale, green chemistry, and POGIL, among others ) has enhanced my own chemistry teaching immeasurably in recent years and, I believe, has greatly benefited my students as well.

Getting involved locally

My ACS local section, the Northeastern Section, is very active in Boston and the surrounding area, with a plethora of universities and biotechnology companies nearby, and a large community of ACS members. The local section helps support the first phase of the USNCO competition, as students compete locally for the honor of being nominated to move on to the national competition. Students from across the Northeastern Section are competitive in USNCO, and teachers regularly have their students participate in ACS-related events. We have had local students who progressed on to both the national and international level of competition in recent years.

It was at the local level where I first got involved with writing chemistry test questions. I began by using published exam questions from ACS and other sources. Writing challenging questions and maintaining a balance of topics throughout the exam were skills I improved upon as the years went by. I always had several proofreaders helping me, including both high school and college level educators, who offered editing and stylistic advice as well as modifications so as to not convey any vague or inferred meanings.  

Our local section has always opted to create our own entry-level USNCO examination. Given the strength of our students competing for the USNCO, we decided to create a longer and more challenging local examination. Statistical analysis of exam results over the years has validated this decision.

As exam administrator, I was tasked with creating questions not just for my first-year high school sophomores, but more recently for our section’s top first- and second-year students as well. Using past exams as a guide, the multiple-choice questions ranged across the dozen or so typical topics in secondary school chemistry.

Eventually, this experience at the local level led me to be invited to submit questions to the ACS Examinations Institute, where I came to know Dwayne and Lucy Eubanks, longtime exam writers for the ACS who are renowned for crafting standardized chemistry exams.

National-level involvement

Across the U.S., each local section promotes a minimum of 10 students to move on to the national level competition. The number of students from each section eligible to sit for the USNCO is determined by the number of ACS members per section. Since 1984, the USNCO exam has been made up of three parts:

  • Part I — a section with 60 multiple-choice questions that resembles the multiple-choice section of the AP Chemistry exam, but harder. (90 minutes)
  • Part II — an 8-question, open-response section that resembles the free-response section of the AP exam, but longer. (105 minutes)
  • Part III — beginning in 1995, the exam has also included a 2-question laboratory practical section. (90 minutes)

After I had volunteered at the local level for several years, Lucy recommended me as a new member of the USNCO Part III Laboratory Practical Task Force. Devising open-ended laboratory experiments fed my interest in teaching students through inquiry and experimental design at a time when microscale, POGIL, and other non-traditional methods were at the forefront of ACS National Meeting’s HS Days, BCCE workshops, and in JChemEd articles on secondary school teaching.

At the time, Cecilia Hernandez headed the USNCO office, and convened the exam writers and Coordinators each fall to discuss and review the past year’s exam and the upcoming year’s exam schedule. I attended my first USNCO meeting at the Air Force Academy in Colorado Springs. Because the USNCO Study Camp (the next level of competition for the USNCO) was also held in this location, we exam writers could see this aspect of the USNCO process firsthand.

The top 20 USNCO test-takers from across the U.S. are eligible to attend the live-in camp (which during the pandemic has met online), a rigorous two-week morning-to-evening classroom and laboratory preparation for the International Chemistry Olympiad (IChO). Having served as Mentor at the camp, I can attest to the grueling preparation that students undergo. In preparation for the camp, student participants receive, courtesy of ACS, a dozen or so chemistry texts that range from physical to organic and biochemistry. At the end of the camp, exams determine the top four students to represent Team USA at the IChO.

In the 1990s and 2000s, the exam writers for all three parts of the USNCO met annually to discuss and review the previous year’s exam and offer changes to the upcoming year’s exams. Meetings have been held at locations around the U.S. that were important to some aspect of the USNCO, including the Air Force Academy, as well as Clemson University, Ames and Milwaukee (where the Exams Institute was located), and Washington DC, home to the ACS K–12 Education offices.

Influence of professional development

Attending BCCEs and workshops over the years exposed me to so many creative educators and their novel, thoughtful lab designs and demonstrations. These included work from Lee Marek, Bob Becker, Laura Slocum, Sally Mitchell, and others in the world of secondary chemistry education whom I worship. When creating exam questions, I still draw from the NSF-funded Laboratory Demonstrations summer workshop at Hope College 30 years ago, led by Eugene Jekel. Many of the participants at those NSF workshops at Hope have gone on to make names for themselves in secondary chemistry education. 

After so many years, all of this work continues to feed my interest in promoting novel, creative lab work for our students. As for my students, many benefit from their experience with the USNCO, as they report annually in the post-exam reflection I ask them to share after they have completed the exam. Those who advance beyond the USNCO to the Study Camp and the IChO are immediately recognized by colleges as top chemistry students nationwide — a worthy distinction, given the reputation of ACS.

Evolution of the exam

During my many years of involvement with USNCO, I’ve seen the exam evolve and improve. Part III, the lab practical component, became a part of the USNCO in 1995 and was chaired then by Michael Tinnesand. By the early 2000s, I had assumed the role of USNCO Part III Laboratory Practical Task Force Coordinator, which I held for 10 years.

The Task Force was made up of several secondary and college educators, and several industry members. Task Force members would come up with ideas for labs, which I then tested with some of my students and colleagues. Based on our review of the results, we decided which two (always one more quantitative and the other more qualitative) would be suitable for that year’s USNCO.

Examples of qualitative practicals have included such classics as unknown solution and metal determination, and many variations. Quantitative practicals, meanwhile, have included titrations, molar mass, and rate law determination. Seth Brown at Notre Dame and Arden Zipp at SUNY-Cortland would fact-check and advise on the suitability of the two selected lab practicals. We strove to keep materials and chemicals to a minimum, never including open flame or chemicals recognized to be toxic or environmentally nasty.

After seven or eight years of developing Part III content, we had exhausted the standard lab practicals already mentioned — so we began to select weirder and more novel lab problems. Many drew from articles in JChemEd or other chemical education sources. Of these, I recall that two of the more interesting ones were finding the thickness of a galvanized washer in zinc atoms, and determining absolute zero1 given nothing more than a hot plate, thermometer, graduated cylinder, and electronic scale.

While I consider this part of the exam to be quite valuable, I recall reading Coordinators’ mixed feedback that we received on surveys following the exam administration. Some complained about having a laboratory component, while others thought the inquiry and experimental design were important parts of the USNCO experience. Some were concerned that the laboratory practicals were biased in favor of students who came from courses where this sort of inquiry and lab work was performed (yes, of course they are!). One year, one lab involved a side reaction that produced a microscale amount of SO2(g). This led one coordinator to complain that no student should be able to detect the odor of this gas. Our assumption on the Task Force was that students from strong chemistry learning settings had received a rich exposure to the hands-on experiences involved in experimental design and laboratory exposure.

We also learned from each exam that we needed to be very explicit with directions and explanations of material use. Some instances that stand out in my mind include:

  • A lab involving rate of reaction that used peroxide and a russet potato. This set off a firestorm among Coordinators: Were the potatoes to be peeled? Could we substitute red or fingerling potatoes?
  • Another lab involved calculating the volume of gas needed to fill a provided balloon to simulate the gas filling a car airbag. The instruction was to determine the volume of gas needed to make the balloon ‘plump.’ This set off another raging concern from Coordinators: What exactly did ‘plump’ mean?
  • Yet another experiment involved Drano (we often employed commercial products to allow students to see chemistry in their daily lives). Reading through the Preliminary Instructions, it seemed clear to us that solid Drano was to be used to make a solution, which could then be used to measure the heat of reaction. When we read the Coordinators’ feedback, however, we learned that some sections had used the liquid form of the product, which didn’t serve the purpose of the experimental design.

Typically, questions in the lab practicals would start out with an idea or a variation of a known experiment. This would be passed around the Part III Task Force members, who would then refine and test the question experimentally, making sure the wording was clear and understandable to students, and assessing how much time the experiment would take. In most cases, we were able to come up with great, challenging, thoughtful questions that forced students to apply their chemical knowledge to two novel lab practical questions.

Exam assessment

Chairs of each of the three parts of the USNCO, along with several additional related members, make up the Grading Team, which meets the week after the National Exam is administered in late April. It is always a fun weekend grading exams together, reviewing the statistical analysis of the scores, and enjoying the comradery of the team members.


So much research around best practices in secondary chemistry education point to the use of inquiry and experimental design in offering ‘real science’ experiences for our students. Various JChemEd articles have reflected the debate over ‘cookbook’-style laboratory procedures versus experimental design.

In looking back over these articles, however, I think the debate missed the point; we teach recipe-like procedures to emphasize following directions, introduce proper laboratory technique, and stress safety before using more open-ended laboratory work. It should never be all one or the other, but rather a mix of the two styles for best practices.2

One cannot venture into the creative and untested without first being well familiar with traditional methods and practices. This extends beyond chemistry to science and the arts. I liken this to Picasso’s renown for invention and creativity, forming entirely new genres in painting only after being formally and classically trained. In the words of Russian-American novelist Vladimir Nabokov, himself a trained and published lepidopterologist (specialist in butterflies), “There’s no science without fancy, no art without facts.”

In 2020 the Covid-19 pandemic put a pause on the lab practical portion of the exam for two years. With the return to normalcy, it is hoped that this portion of the national exam will resume in 2022 and continue to receive support from Coordinators across the U.S. Though I no longer serve as the Task Force Coordinator, I continue in my role as USNCO Coordinator for our section, a role I have cherished for over 25 years in supporting our section’s top students and their teachers.

You can get involved too!

USNCO is always looking for more teachers to get involved. The ACS Science Outreach Program is your one-stop-shop for beginning your involvement. They can tell you how to communicate with your local section USNCO Coordinator, who is likely to need assistance with the publicizing and administration of both the local section and USNCO exams.

As the new school year begins, other steps you can take include:

  • enter your students in your section’s local exam competition
  • learn more about the USNCO program through ongoing webinars
  • become involved with exam writing through your local section as a way to improve your own question writing skills while learning what is happening in chemical education at the national level

In short, nothing in my years of teaching high school chemistry has been more professionally rewarding than my longtime involvement with the USNCO program!


  1. Kim, M.; Kim, M.S.; Ly, S. A Simple Laboratory Experiment for the Determination of Absolute Zero, J. Chem. Educ. [Online] 2001, 17, 238–240. (accessed Aug. 6, 2021).
  2. Bruck, L.; Towns, M. Preparing Students To Benefit from Inquiry-Based Activities in the Chemistry Laboratory: Guidelines and Suggestions, J. Chem. Educ. [Online]. 2009, 86, 820–822. (accessed Aug. 6, 2021).

Photo credit:
(article cover) Image courtesy of USNCO