日本水大賞委員会（事務局：公益社団法人日本河川協会）(Japan Water Prize Committee; secretariat: Japan River Association)
Japan's official national selection for the Stockholm Junior Water Prize, run by the Japan Water Prize Committee: high school students submit water-related research projects, and the Grand Prix team represents Japan at the international final during World Water Week in Stockholm. The 2028 call has not been published yet.
公益社団法人日本気象学会 教育と普及委員会 (Meteorological Society of Japan, Education and Outreach Committee)
A free research presentation session held during the Meteorological Society of Japan's spring meeting, where junior high, high school and early-KOSEN students present their own weather, climate or atmospheric research to professional meteorologists. The 2027 call has not been published yet.
一般財団法人 高度情報科学技術研究機構 (RIST, Research Organization for Information Science and Technology)（共催：理化学研究所計算科学研究センター ほか）
A free two-day event at four supercomputing centres in which junior high, high school and KOSEN students with C/C++ experience use the supercomputer Fugaku to tackle advanced AI and parallel-computing tasks. The 2027 edition has not been announced yet.
A session at the Astronomical Society of Japan's spring annual meeting where junior high, high school and kosen students present astronomy and space research, free of charge.
A free poster session for high school students held at the Palaeontological Society of Japan's January regular meeting, where students present research on fossils, evolution, ecology, stratigraphy or sedimentary environments to palaeontologists and compete for poster awards. The 176th meeting takes place at Waseda University, Tokyo, on 29-31 January 2027.
A fully funded hybrid program on sustainability and STEM: 12 weeks online followed by 4 weeks in Brazil, China, Egypt or India; AFS Japan selects about five scholars from Japan. The 2027 call has not been announced yet.
A Kyushu University Faculty of Science summer project that selects about four students each in chemistry and biology for a one-week, small-group university-level seminar and lab course, ending with a public presentation.
A national film contest for high school students run by the NPO Eiga Koshien, accepting films of any theme or genre up to 45 minutes, with the best works screened and awarded at a live event in Tokyo.
高校生平和大使派遣委員会 (High School Peace Ambassadors Dispatch Committee) / 高校生平和大使全国支援委員会
A citizen-run program, started in Nagasaki in 1998, that selects high school students from across Japan each year to carry the message of the atomic-bombed cities and the signatures of the High School Students' 10,000 Signature Campaign to the United Nations Office at Geneva. The call for the 30th cohort has not been published yet.
Fukuoka Prefecture's selective short-term overseas programme for high school students: a Silicon Valley tech and entrepreneurship course and work-experience courses in Hawaii, Australia and Singapore, with travel and lodging paid by the prefecture.
A national championship for high school calligraphy performance teams, with a video-and-photo preliminary in seven regional blocks and a live final in Shikokuchuo, Ehime, Japan's 'paper town'.
東京大学大学院数理科学研究科 (Graduate School of Mathematical Sciences, The University of Tokyo)
A free half-day event at the University of Tokyo's Komaba campus (also online) where women who studied mathematics and UTokyo mathematicians talk about the appeal of mathematics and math-based careers, with a lunch meeting with math students and faculty.