MIT PRIMES-USA
A free, year-long remote mentored research program from MIT's math department in which high school juniors and sophomores from outside the Boston area work on original, unsolved math problems with guidance from MIT researchers.
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Art of Problem Solving (AoPS) Online
Rigorous online courses & problem‑solving community; core resource for contest‑math and proofs (AoPS classes in algebra, NT, geo, combinatorics).
Bay Area BioGENEius Challenge (Applied Math Track)
A high-level research competition. Winning projects often use bioinformatics (statistical analysis of genetic data).
LSU Virtual Math Circle
A virtual research-oriented course where high schoolers study material beyond the standard curriculum with a research focus.
Stanford Pre‑Collegiate University‑Level Online Math & Physics
Year‑long or term‑long online courses (e.g., Number Theory, Linear Algebra, Real Analysis) for advanced high schoolers worldwide.
STARS at Cold Spring Harbor
While based in NY, they offer virtual bioinformatics training where you use algorithms to analyze DNA sequences.
Berkeley Lab Experiences in Research (EinR)
Research placements at Lawrence Berkeley National Lab with many projects involving modeling, computation, and data analysis in scientific contexts.