List of Olympiads for students.
The International Mathematical Olympiad (IMO) is the World Championship Mathematics Competition for High School students and is held annually.
The official site for the International Junior Science Olympiad (IJSO).
The IOI is the most prestigious computer science competition in the world for secondary school students. UNESCO and IFIP are patrons.
The official site for the International Linguistics Olympiad (IOL).
The International Medicine Olympiad (IMDO) is an international competition in medicine-related fields of biology for high school students.