For students planning to apply for majors in biology, medicine, or related life sciences fields, international biology competitions are a recognized pathway to strengthen college applications. This guide covers four leading international biology competitions and provides preparation advice tailored by grade level, so you can choose the right competition and start at the right time.
Brain Bee World Brain Science Competition
Junior Division (Grades 5–8)
For students in Grade 8 or below, the Brain Bee Junior Division offers a focused entry point into competitive science. Unlike broad biology olympiads, this competition concentrates exclusively on neuroscience and brain science.
Format: Two components — a written exam (40 questions: fill-in-the-blank and multiple-choice, 1 point each) and a team poster presentation (40 points, with the team’s score applied to each member).
Content: Basic brain structures, foundational neurobiology, nervous system disorders, sensory perception, and brain development. The focus is on fundamental concepts in brain anatomy and function.
Awards: At the regional level, first, second, and third prizes cover approximately 40% of participants. The Junior and Senior divisions are ranked separately, though during the China regional stage, participants from both divisions are pooled for advancement.
Preparation Note: Neuroscience is a specialized niche with limited coverage in standard school curricula, so dedicated independent study is required. Budget significant preparation time.
Senior Division (Older High School Students)
The Brain Bee Senior Division follows a similar structure to the Junior Division but increases difficulty, breadth, and depth substantially. It carries high prestige for students pursuing advanced studies in neuroscience or brain science.
Content: Foundational neurobiology and brain science, expanding into specific nervous system diseases and treatments, brain injuries, neurological impacts of substance abuse, and the effects of environment on brain development. Neuroanatomy is heavily emphasized, requiring dedicated memorization of complex brain structures.
Format: Three segments — written exam (50 questions, 1 point each), specimen identification (13 questions, 2 points each), and case/video diagnosis (8 major questions, 3 points each).
BBO — British Biology Olympiad
Organized by the Royal Society of Biology and running since 1995, the BBO is one of the longest-running and most influential high school science competitions in the UK. It serves as the primary selection process for the UK team at the International Biology Olympiad (IBO) and is widely valued for biology and medicine applications at UK G5 universities.
Content: 20% Cell Biology, 15% Plant Anatomy and Physiology, 25% Animal Anatomy and Physiology, 5% Animal Behavior, 15% Genetics and Evolution, 15% Ecology, 5% Taxonomy. The syllabus extends beyond standard A-Level into first-year university biology.
Format: Individual written exam, 90 minutes, available in Chinese and English. Questions include multiple-choice (single and multiple answer) and fill-in-the-blank (primarily calculation-based).
Awards: Based on UK national cutoff scores — Gold (top 5%), Silver (top 15%), Bronze (top 30%), High Commendation (top 45%), Commendation (top 60%). The overall award rate is approximately 60%.
Preparation: The exam features a large number of questions (reaching 297 in recent years), making time management critical. The scope is clearly defined and relatively accessible compared to USABO, but pacing must be practiced explicitly. A BBO Gold medal is particularly valuable for applications to UK universities.
USABO — USA Biology Olympiad
The USABO is organized by the Center for Excellence in Education (CEE) and serves as the US national selection pathway for the International Biology Olympiad (IBO). It is widely regarded as one of the most academically rigorous STEM competitions available to high school students, attracting over 10,000 participants in the US each year.
In China, USABO runs as BIO-USACN under ASDAN. The 2026 China exam was held on April 4, 2026. Students targeting the 2027 season should begin preparation now — the next China region exam date will be announced later in 2026.
Content: Cell biology, molecular biology, biotechnology, plant physiology, animal physiology, evolutionary biology, systems biology, genetics, and animal behavior — at college freshman level.
Format: 50 multiple-choice questions in 50 minutes, entirely in English.
China Region Awards: Top Gold (top 5%), Gold (top 15%), Silver (top 30%), Bronze (top 45%). Recent raw score cutoffs: Gold ~40/50, Silver ~33/50, Bronze ~25/50.
Preparation: The USABO and BBO syllabi overlap significantly, making dual preparation efficient. However, USABO is notably more demanding — it tests fine details, professional depth, and logical reasoning under strict time pressure. Strong English and a college-level biology foundation are essential.
iHOSA — Future Health Professionals Challenge
The iHOSA challenge focuses on current biological and health-related issues. It is structured into three components: the Academic Core Challenge (ATC), which covers foundational biology similar to AP/IB exams; the Community Engagement component (BCE), which involves public service projects such as creating educational workshops or public service announcements; and the Clinical/Professional Challenge (CCE), which tests specialized knowledge in areas like physiology, pathology, and biotechnology.
Content: Animal physiology, plant physiology, cell physiology, genetics, molecular biology, ecology, and health topics. The BCE component requires communication skills and media awareness. The CCE overlaps with psychology, microbiology, nutrition, biochemical pathology, and biotechnology.
Awards: All participants receive a certificate of participation. Top performers receive Gold (top 5%), Silver (top 15%), and Bronze (top 30%) at both national and regional levels.
Preparation: Moderate difficulty for students already studying AP, IB, or A-Level biology. Recommended preparation: 1–2 months for well-prepared students, 3–4 months for those needing to build foundational knowledge. The national round adds approximately 30% more content than the preliminary stage.
Recommended Preparation Timeline by Grade Level
- Grade 8 and below: Begin Brain Bee Junior Division preparation early in the academic year.
- Grade 9: Continue Brain Bee if interested in neuroscience; begin exploring iHOSA and BBO content.
- Grade 10: Start iHOSA preparation early in the year. Begin BBO prep mid-year.
- Summer between Grade 10 and 11: Begin comprehensive BBO and iHOSA consolidation.
- Grade 11 (Fall Semester): Begin intensive preparation for BBO and USABO. Students deeply interested in neuroscience may also prepare for the Brain Bee Senior Division.
This guide covers the essential details of four leading international biology competitions. Use it as a reference for academic planning, and begin preparation with enough lead time to build a strong knowledge base before exam season.