MIT research programs for high school students: RSI, PRIMES, MITES and Beaver Works

MIT's name attaches to four quite different high school programmes, only one of which is run by MIT's own admissions-adjacent outreach, and only three of which are free.

Sorting out which is which matters, because they have different deadlines, different eligibility rules, and vastly different odds.

What MIT research programs exist for high school students?

Four, plus a set of smaller offshoots.

MITES Semester was previously called MOSTEC. If you find a page referring to MOSTEC, it is out of date — and several are, including MIT's own outreach application portal, which in September 2026 was still displaying 2023 dates.

How competitive is RSI?

Under 2.5%, and it is one of the only programmes in this entire sector that will tell you.

The Center for Excellence in Education states on its FAQ that RSI "receives over 2,500 U.S. applications and 600 international applications each year and accepts less than 2.5% of applicants." The cohort is 100 students.

For scale, that is roughly a quarter of Harvard's undergraduate admission rate, for a six-week summer programme.

RSI also has the tightest eligibility of the four. Juniors only — the FAQ is explicit that "High school juniors are eligible. High school seniors are not" — and you must be 16 by 1 July. US applicants apply directly to CEE with PSAT, SAT or ACT scores; the recommended thresholds are demanding, around 750+ SAT Math and 700+ EBRW. International students apply through country-specific partner procedures rather than to CEE directly, which is the detail most international students miss.

The structure is one week of intensive STEM coursework, five weeks of individual research with a scientist mentor at MIT or another Boston-area institution, and a final week of written and oral conference-style presentation.

What is MIT PRIMES and who can do it?

A free, year-long mathematics and bioinformatics research programme run by MIT's Department of Mathematics — and the one with a genuine, published 2027 deadline.

PRIMES is for sophomores and juniors resident in Greater Boston, because it is an in-person after-school programme. PRIMES-USA is the same for students elsewhere in the United States. International students are not eligible and are directed to CrowdMath, MIT's open online research project, instead.

The year runs in four phases: reading from January to mid-March, research from mid-March to mid-June, independent study through August, and write-up and presentation from September to December. Expect at least ten hours a week during the first two phases. That is a substantial commitment layered on top of a school year, and it is the main reason students drop out.

Mentors are usually MIT graduate students and postdocs. Juniors may work individually or in groups; sophomores work in groups only.

The deadline is 2 November 2026, 11:59pm EST, with recommendation letters due 6 November and decisions by early January 2027. Of all the programmes on this page, this is the one with a real, currently published date — and it is the nearest.

PRIMES does not publish an acceptance rate. Its page says only that "a small number of candidates is admitted."

How do MITES Summer and MITES Semester differ?

One is six weeks in Cambridge; the other is six months on a laptop. Both are free, and both are closed to anyone without US citizenship or a green card.

MITES Summer is residential: five college-level courses in maths, life sciences, physics, humanities and a project-based elective, 9am to 5pm on weekdays, plus lab tours, seminars and college admissions counselling. MIT covers all programme costs; students pay only travel, and travel scholarships exist.

MITES Semester runs online over six months: two STEM courses, live evening classes, weekly webinars and mentoring, and a team project presented at a symposium. Around 25 to 30 hours a week over the summer, dropping to 3 to 5 hours a week in the autumn.

Both are for students in 11th grade at the time of application. Applications open in November and close on 1 February, with decisions in mid-to-late April. Neither publishes an acceptance rate.

One caution: MIT had not published 2027 dates for either as of September 2026, and its FAQ says so explicitly.

Is Beaver Works free?

Only for families under a $200,000 threshold. Above it, $3,000.

MIT Lincoln Laboratory's Beaver Works Summer Institute charges nothing to families with household income and assets under $200,000, and $3,000 to everyone else, verified through a financial application. Housing is not included either way — there is no residential component, and in-person students must arrange accommodation with adult supervision.

It is also the only one of the four with published 2027 dates: 5 July to 1 August 2027, with free online prerequisite courses opening 1 February 2027 and teacher nominations closing 31 March.

The structure is unusual and worth knowing. Selection depends substantially on completing a mandatory self-paced online prerequisite course before the summer application is even sent out. Project areas include autonomous racing vehicles, autonomous air and underwater vehicles, quantum computing, radar, medical devices and assistive technology — engineering rather than research in the paper-producing sense.

International students may take the free online courses but cannot attend the summer programme.

Which should you apply to?

If you are a US-resident sophomore or junior interested in mathematics, PRIMES is the immediate one, because 2 November 2026 is weeks away and nothing else has a live deadline.

If you are a US junior with strong maths scores and a genuine research interest, apply to RSI in December, accept that the odds are worse than any university you will apply to, and have a fallback.

If you are a US citizen or permanent resident in 11th grade, MITES in either format is free and substantial, and MITES Semester works around a school year.

If you are an international student, three of these four are closed to you and the fourth requires a national partner body. This is the single most common disappointment in this area, and it is better discovered in September than in February.

What if none of them take you?

Which is the statistically likely outcome. RSI alone rejects roughly 3,000 students a year, most of them excellent.

The routes that remain are a local university lab, an independent project using public data, or a paid mentorship programme. The first is free and difficult; the second is free and requires self-direction; the third costs $3,000 to $11,800 and buys structure.

Where we fit

The Oxford Centre for Advanced Research runs 1:1 online mentorships with PhD candidates and early-career researchers at Oxford, Cambridge, other leading UK universities and Ivy League institutions. The Oxford Scholar Programme is £2,000 — about $2,600 — for ten contact hours over ten to fourteen weeks. The Oxford Publication Fellowship is £3,400, roughly $4,400, and is built around submission to the Oxford Journal of Student Scholarship, the Journal of Research High School or Vanderbilt's Young Scientist Journal.

We accept approximately 60% of applicants. Self-reported and unaudited — as is every figure any competitor publishes, and unlike RSI's, which is at least stated by the programme running it.

Nothing we offer is a substitute for RSI or PRIMES, and we would not claim otherwise. Those are free, extraordinarily selective, and carry a name. What we offer is a programme with no citizenship requirement, no geography requirement, and rolling admission — which matters because the MIT programmes exclude most of the world before merit is considered.

The date that matters right now

2 November 2026, for MIT PRIMES and PRIMES-USA.

It is the only genuinely open deadline among the four, and it is the one students discover too late.

Frequently asked questions

Which MIT program is the most competitive?

RSI, by a wide margin and by its own published figures. It receives over 2,500 US applications and 600 international applications a year for about 100 places, accepting under 2.5%. None of the other MIT-linked programmes publishes an acceptance rate, so direct comparison is not possible — but PRIMES describes admitting only 'a small number of candidates'.

Is RSI actually run by MIT?

It is hosted at MIT but run by the Center for Excellence in Education, a separate non-profit. Students are placed with scientist mentors at MIT and Boston-area institutions. The distinction matters mainly because RSI applications go through CEE rather than MIT admissions, and international applicants apply through partner-country bodies rather than directly.

Can international students apply to MIT programs?

Barely. MITES Summer and MITES Semester require US citizenship or a green card. MIT PRIMES is open only to US residents and directs international students to CrowdMath instead. Beaver Works requires living and attending school in the US. RSI accepts international students only through country-specific partner nominating bodies.

Is MIT Beaver Works free?

Only conditionally. It is free for families with household income and assets under $200,000, and costs $3,000 above that threshold, verified through a financial application. Housing is not included at either price — there is no residential component, so in-person students arrange their own accommodation with adult supervision.

What is the difference between MITES Summer and MITES Semester?

MITES Summer is six weeks residential at MIT with five college-level courses. MITES Semester — previously called MOSTEC — is six months online with two STEM courses, weekly mentoring and a team project presented at a symposium. Both are free and both require US citizenship or permanent residency.

When is the deadline?

MIT PRIMES closes 2 November 2026 for the 2027 cycle, with recommendations due 6 November. MITES closes 1 February. RSI has closed on the Wednesday of the second full week in December in recent years; its 2027 date was unpublished as of September 2026. Beaver Works nominations close 31 March 2027.