Named in honor of the Mandelbrot set, the Mandelbrot Competition is a mathematics competition founded by Sam Vandervelde, Richard Rusczyk and Sandor Lehoczky that allows high school students to compete individually and in four-person teams.
The Mandelbrot is a "correspondence competition," meaning that the competition is sent to a school's coach and students compete at their own school on a predetermined date. Individual results and team answers are then sent back to the contest coordinators. The most notable aspects of the Mandelbrot competition are the difficulty of the problems (much like the American Invitational Mathematics Examination and harder American Mathematics Competition problems) and the proof-based team round. Many past medalists at the International Mathematics Olympiad first tried their skills on the Mandelbrot Competition.
The Mandelbrot Competition was started by Sam Vandervelde, Richard Rusczyk and Sandor Lehoczky while they were undergraduates in the early 1990s. Vandervelde still runs the competition. Rusczyk now manages Art of Problem Solving Inc. and Lehoczky enjoys a successful career on Wall Street.
Contest format 
The individual competition consists of seven questions of varying value, worth a total of 14 points, that students have 40 minutes to answer. The team competition is a proof-based competition, where many questions are asked about a particular situation, and a team of four students is given 40 minutes to answer.
The Mandelbrot Competition has two divisions, currently referred to as National and Regional. Questions at the National level are more difficult than those at the Regional level, but generally have overlap or concern similar topics. For example, in the individual competition, the National competition will remove some of the easier Regional questions, and add some harder questions. In the team competition, the topic will be the same but the National level will give fewer hints.
Recent winners 
The top four high schools in the 2003–2004 National division were Academy for the Advancement of Science and Technology, NJ; Thomas Jefferson High School for Science and Technology, VA; Stuyvesant High School, NY; and the Illinois Math and Science Academy.