Math Madness by AreteLabs
Season-long online team competition with weekly or biweekly matches, similar to an online math league for middle and high school teams.
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AMC 10/12 (MAA American Mathematics Competitions)
National contest series leading to AIME and USAMO, administered at schools or online through registered hosts with fall test dates.
ASA Statistics Project Competition
National competition where students design and carry out their own statistical studies and present results, open to grades 7-12.
Wharton High School Data Science Competition
Annual data science competition focused on hockey analytics where high school teams analyze real sports data and compete for recognition.
Berkeley Chess School Scholastic Tournaments
Weekly USCF-rated scholastic chess tournaments held across the Bay Area (Berkeley, Walnut Creek, Alameda) and open to K-12 players including high schoolers, run by the Berkeley Chess School since 1982.
Berkeley Math Tournament (BMT)
Flagship Bay Area high school math tournament with both online and in-person editions at UC Berkeley, recurring annually with advanced problem-solving challenges.
CalChess Grade Level Championship
A statewide scholastic chess championship held in the South Bay (Milpitas) where California K-12 students, including high schoolers, compete by grade level for state titles. Requires an active USCF membership.