USA Biology Olympiad

No. The USABO Open Exam is limited to students in grades 9-12, so eighth graders and younger cannot register. Ninth graders can and should sit it early: many eventual National Finalists take the Open Exam once in 9th or 10th grade simply to learn the question style, then push further each year. Note also that a graduating senior who has formally enrolled in an undergraduate program is no longer eligible.

Students cannot self-register for the USABO. A school or a USABO-authorised test centre must register first, pay a flat $125 per school, and then enrol its students. The fee covers every student at that school, and registered schools are not allowed to charge students an extra service fee, so the practical step is to ask the biology teacher to start the process early. Homeschooled students arrange directly with USABO before the deadline and sit the exam at a local high school.

It is online but not at-home. The USABO Open Exam must be taken in person at the registered school or authorised test centre, proctored by a teacher, inside the window set by the Center for Excellence in Education — 3 February 2027 at 4pm ET for the 2027 season. The 120-minute Semifinal is proctored the same way. This applies to every Irvine public and private high school alike, so the teacher's involvement is unavoidable.

The Open Exam is a 50-minute multiple-choice paper with no penalty for guessing, broad in coverage but closer to solid high-school level, and open to every registered student. The Semifinal is a 120-minute exam in several parts: Part A multiple choice, Part B multiple choice with more than one answer, Part C multiple true/false, and Part D four short-answer or essay questions on the host country's IBO practical topics. Neither round penalises guessing. Only the top 10% of Open Exam scorers who are US citizens or permanent residents advance to it.

There is no fixed cutoff. USABO advances roughly the top 10% of Open Exam scorers, and the threshold moves each year with paper difficulty; CEE publishes the season's cutoff table afterwards. On the recent 50-point papers the semifinalist line has landed in the twenties. Even without advancing, the top 20% receive an Honorable Mention certificate and the top 30% a Certificate of Merit, both of which can be listed on a college application.

They can sit the Open Exam and earn its certificates, but the Semifinal, the National Finals and US team selection are restricted to US citizens and lawful permanent residents. A student here on an F-1 visa can therefore compete in round one and report the result on applications, but cannot advance further. Students in that position often pair the USABO Open Exam with an olympiad that has no citizenship restriction, such as the British Biology Olympiad.

For the Open Exam, Campbell's Biology on its own is essentially enough. Focus on cell and molecular biology, genetics, animal and plant physiology, ecology and evolution, and spend your time on a full read-through plus past papers rather than on obscure chapters. For the Semifinal and National Finals, Campbell is only the starting point: strong candidates add a specialist text such as Molecular Biology of the Cell and study the current IBO practical topics.

AP Biology is the floor, not the finish line. The USABO Open Exam covers more ground than AP and asks for finer detail, and students who scored a 5 on AP Bio often still fall short of the semifinalist cutoff on their first attempt. A realistic sequence is to take AP Biology in 10th grade, read Campbell and work through past USABO papers over the summer, then target the Open Exam and Semifinal seriously in 11th grade.