From the event website:

"The Berkeley Math Tournament Group hosts and organizes mathematical contests for middle and high school students. In organizing these tournaments, the team strives to encourage mathematical exploration and understanding by introducing concepts not covered in the typical pre-college curricula to students with high mathematical aptitude and interest. Each contest emphasizes collaboration between team members, while still allowing individuals to prove their own ability. Any individual currently enrolled in a pre-college institute for youth is welcome to compete, and accommodations may be made for teams with demonstrated financial need.

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BMT: Berkeley Math Tournament. The spring tournament offers teams of high school students the opportunity to share their interest in mathematics with likeminded individuals and to get a taste of the type of concepts studied in higher mathematics."

For more information, see the Berkeley Math Tournament website.