Here are some competitions to start you off.
USA Mathematical Olympiad
USA Biology Olympiad
U.S. National Chemistry Olympiad
U.S. Physics Team
Siemens Competition in Math, Science & Technology
Regeneron Science Talent Search
Scholastic Art & Writing Awards
Profile in Courage Essay Contest
Ayn Rand Essay Contests
The Concord Review
National History Day
YoungArts
National Spanish Exam
Le Grand Concours
Chinese Proficiency Test (HSK)
National Latin Exam
National Greek Exam
National Italian Examination
