| Application deadline | Unconfirmed — check official site | Unconfirmed — check official site | Unconfirmed — check official site |
|---|
| Cost | Last year's cycle (2026): $5,518; 2027: Unconfirmed — check official site | Unconfirmed — check official site | Last year's cycle (2026): $885–$12,135; 2027: Unconfirmed — check official site |
|---|
| Financial aid | Last year's cycle (2026): 2026 need-based application and program assistance: Up to $5,564. Could assist with the $46 application fee and $5,518 program cost based on family income, family size and available funds; actual award not guaranteed.; 2027: Unconfirmed — check official site | Last year's cycle (2026): U.S. family-income guarantee: Amount: Unconfirmed — check official site. U.S. students from families under $80,000 attended free in 2026.; Full/partial need-based aid and international aid: Amount: Unconfirmed — check official site. Aid available where cost is a barrier; international aid considered case by case.; 2027: Unconfirmed — check official site | Last year's cycle (2026): Need-based Arts & Sciences scholarship: Amount: Unconfirmed — check official site. Available to domestic and international students; amount varies and excludes travel, books/supplies, personal costs, computer, and Wi-Fi.; 2027: Unconfirmed — check official site |
|---|
| Expenses and aid conditions | Last year's cycle (2026): 2026 COSMOS application fee: $46. Nonrefundable; pending fee-waiver review could change when or whether payment was required.; Credit-card transaction fee on program payments: Amount: Unconfirmed — check official site. Approximately 2.5% when paying program costs by credit card; application fee exempt.; 2026 need-based application and program assistance: Up to $5,564. Could assist with the $46 application fee and $5,518 program cost based on family income, family size and available funds; actual award not guaranteed.; Full-financial-aid attendance deposit: $200. Required only for admitted students offered full aid and refunded to the legal guardian after successful completion.; 2027: Unconfirmed — check official site | Last year's cycle (2026): U.S. family-income guarantee: Amount: Unconfirmed — check official site. U.S. students from families under $80,000 attended free in 2026.; Full/partial need-based aid and international aid: Amount: Unconfirmed — check official site. Aid available where cost is a barrier; international aid considered case by case.; 2027: Unconfirmed — check official site | Last year's cycle (2026): Selective Arts & Sciences program application fee: $50. Nonrefundable; waivable for listed financial-hardship criteria. Registration-only programs may not charge it.; Post-admission enrollment deposit: $500. Nonrefundable for Summer Launch, Institutes, and Summer Scholars and deducted from total cost.; Optional 2026 commuter lunch plan for Summer Scholars: $375. Residential Scholars pricing includes room and meals.; Need-based Arts & Sciences scholarship: Amount: Unconfirmed — check official site. Available to domestic and international students; amount varies and excludes travel, books/supplies, personal costs, computer, and Wi-Fi.; 2027: Unconfirmed — check official site |
|---|
| Stipend or pay | Unconfirmed — check official site | Unconfirmed — check official site | Unconfirmed — check official site |
|---|
| Eligibility | Grades 9–12 (provider uses rising grades) | Grades 10–12; Grade timing: Unconfirmed — check official site | Grades 10–12; Grade timing: Unconfirmed — check official site |
|---|
| Additional eligibility | Residency: Attend high school in person in California; Requirement: Be rising into grade 9, 10, 11 or 12 for the program fall year; Requirement: Attend high school in person in California; Requirement: Demonstrate academic excellence and preparation for the selected STEM cluster; Requirement: Complete cluster-specific course prerequisites; Requirement: Live on the host UC campus for the full program; Requirement: Be a first-time COSMOS participant; Exclusion: Students not attending a California high school in person; Exclusion: Students who previously attended any COSMOS program; Exclusion: Applicants outside the rising-grade 9-12 range; Exclusion: Applicants unable to live on campus for the full program; Exclusion: Late application, supporting, payment or admission materials; Exclusion: Assuming a 3.5 GPA is an absolute statewide minimum rather than the published typical profile | Ages 14–18; Residency: Students from the United States and abroad are eligible; international financial aid is case by case; Requirement: Be age 14-18 by the applicable program cutoff; Requirement: Have completed grade 9 or equivalent before the session; Requirement: Not be enrolled full time in a college or university by the program's first day; Requirement: Be available for the entire six-week residential session and comply with dormitory, curfew, visiting, safeguarding, and conduct rules; Requirement: Independently attempt the official application problem set and explain experiments, conjectures, proofs, and partial progress; Requirement: Submit the required recommendation, transcript, form, short answers, and any financial-aid documents; Requirement: Retain scratch work and be prepared to explain reasoning if originality is verified; Exclusion: Applicants outside the age/education window or already full-time college students at program start; Exclusion: Collaborative, copied, AI-assisted, internet-generated, uncited, or inadequately explained problem-set work; Exclusion: Applicants unable to reside for the full six weeks or follow residential/safety expectations; Exclusion: Assuming all eight problems must be solved or that prior advanced courses/research are required; Exclusion: Assuming selection guarantees aid, publication, conference presentation, college credit, recommendation, admission advantage, internship, or job | Citizenship: Domestic and international eligibility varies by program; Arts & Sciences accepts international applicants subject to English and immigration requirements; Residency: National/international for many academic programs; Residency: St. Louis-area residency required for several paid research and environmental programs; Residency: Rural eligibility required for Rural Scholars Academy; Requirement: Select a specific WashU program and meet its grade, academic, course, location, and schedule requirements; Requirement: Summer Scholars applicants are current juniors/rising seniors; Requirement: Summer Institute and Launch applicants generally enter grades 10-12 depending on program; Requirement: Course prerequisites apply to some credit-bearing offerings; Requirement: International applicants may need English-proficiency and visa documentation; Exclusion: No single grade, residence, price, or application rule covers the whole umbrella; Exclusion: Local internships and field programs may exclude non-St. Louis-area applicants; Exclusion: Participation does not guarantee WashU undergraduate admission or admissions advantage; Exclusion: Credit transfer and high-school-credit recognition are controlled by the receiving school |
|---|
| Session dates or duration | Catalog terms: 4 weeks; 2027: Unconfirmed — check official site | Catalog terms: 6 weeks; 2027: Unconfirmed — check official site | Catalog terms: 1–8 weeks; 2027: Unconfirmed — check official site |
|---|
| Format | In person | In person | In person / Online / Hybrid |
|---|
| Housing and supervision | Residential. Supervision and housing details: Unconfirmed — check official site | Residential. Supervision and housing details: Unconfirmed — check official site | Unconfirmed — check official site |
|---|
| Location | Davis, California, Irvine, California, Los Angeles, California, Merced, California, San Diego, California, Santa Cruz, California, UC Davis, UC Irvine, UCLA, UC Merced, UC San Diego, UC Santa Cruz | Boston, Boston University campus, Massachusetts | St. Louis, Missouri, Program-specific local field sites |
|---|
| Selection and application | Selection: Each of six campuses accommodates roughly 160-200 students, and clusters typically enroll 20-25 with a commonly reported 5:1 student-to-faculty ratio. Admissions are competitive and based on academic merit relative to the selected topic, but applicant count and statewide acceptance rate were not published. Application materials: One personal statement; One required teacher recommendation, with two recommended | Selection: About 80 high-school students are selected through demonstrated mathematical thinking in the problem set, academic context, recommendation, transcript, and short answers. PROMYS does not publish the current applicant count or acceptance rate. Application materials: One recommendation | Selection: Selectivity ranges from registration-based online courses to holistic selective residential programs and competitive paid research. WashU does not publish one umbrella application count, acceptance rate, capacity, waitlist, or rubric; each linked unit controls its process. Application materials: For selective Arts & Sciences programs: short essays, $50 fee or qualifying waiver, transcript, and one teacher recommendation; Separate local-residency, research, portfolio, financial, rural, or employment materials for other WashU programs |
|---|
| Official sources | Source 1 · checked 2026-08-22Source 2 · checked 2026-08-22Source 3 · checked 2026-08-22Source 4 · checked 2026-08-22Source 5 · checked 2026-08-22Source 6 · checked 2026-08-22Source 7 · checked 2026-08-20 | Source 1 · checked 2026-08-20Source 2 · checked 2026-08-20Source 3 · checked 2026-08-20Source 4 · checked 2026-08-20Source 5 · checked 2026-08-20Source 6 · checked 2026-08-20 | Source 1 · checked 2026-08-22Source 2 · checked 2026-08-22Source 3 · checked 2026-08-22Source 4 · checked 2026-08-22 |
|---|
