| Application deadline | Unconfirmed — check official site | Unconfirmed — check official site | Unconfirmed — check official site |
|---|
| Cost | Unconfirmed — check official site | Last year's cycle (2026): $5,518; 2027: Unconfirmed — check official site | Last year's cycle (2026): $3,900; 2027: Unconfirmed — check official site |
|---|
| Financial aid | Unconfirmed — check official site | 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 | Unconfirmed — check official site |
|---|
| Expenses and aid conditions | Unconfirmed — check official site | 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 | Unconfirmed — check official site |
|---|
| Stipend or pay | Unconfirmed — check official site | Unconfirmed — check official site | Unconfirmed — check official site |
|---|
| Eligibility | Unconfirmed — check official site | Grades 9–12 (provider uses rising grades) | Grades 9–12; Grade timing: Unconfirmed — check official site |
|---|
| Additional eligibility | Requirement: American Legion Boys State gives selected high-school students hands-on experience creating and running a mock state government. Schools and local Legion posts usually recommend, interview and select delegates. Requirements, dates and costs are set by the state programme.
Two delegates from each Boys State programme may advance to Boys Nation in Washington, D.C. The national 2027 session is announced for summer, but that is not a shared Boys State application deadline or venue. Sponsorship and family-paid costs must be checked locally. | 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 | Minimum age 14; Residency: Currently studying and residing in the United States; Requirement: Be at least 14 by program start; Requirement: Be a current high-school student; Requirement: Demonstrate good programming ability in Python, Java, C/C++, or another language; Requirement: Understand computer-science fundamentals; Requirement: Commit to the full-time six-week commuter or virtual schedule; Requirement: Provide one science, mathematics, or computer-science teacher reference; Exclusion: Applicants under 14 at program start; Exclusion: Applicants not currently studying and residing in the United States; Exclusion: Applicants unable to commit to the complete schedule; Exclusion: Applicants whose skills do not match available mentor projects |
|---|
| Session dates or duration | Unconfirmed — check official site | Catalog terms: 4 weeks; 2027: Unconfirmed — check official site | Catalog terms: 6 weeks; 2027: Unconfirmed — check official site |
|---|
| Format | Unconfirmed — check official site | In person | In person / Online |
|---|
| Housing and supervision | Unconfirmed — check official site | Residential. Supervision and housing details: Unconfirmed — check official site | Non-residential. Supervision and housing details: Unconfirmed — check official site |
|---|
| Location | Unconfirmed — check official site | 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 | Stony Brook, New York (commuter track), United States residency and study required; virtual track for students unable to commute |
|---|
| Selection and application | Unconfirmed — check official site | 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: Mentors evaluate application strength and fit to limited project capacity; each accepted student receives a mentor assignment with the offer. Application materials: Essay of no more than two pages on a computing or data-analytics interest, motivation, programming skills, and past projects; One science, mathematics, or computer-science teacher recommendation submitted separately |
|---|
| Official sources | Source 1 · checked 2026-10-09Source 2 · checked 2026-10-09Source 3 · checked 2026-08-21 | 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 2026-08-20 |
|---|