Arizona · Nonprofit
San Tan Montessori School Inc
San Tan Montessori School Inc (Arizona) receives grants from 6 organizations whose IRS filings report $53,271 to it, the largest being AMERICAN ONLINE GIVING FOUNDATION INC ($24,389). 2 of them have funded it in more than one year, and 63% of the money arrives through donor-advised or pass-through sponsors rather than from an institution directly.
- Revenue FY2025
- $11M
- Funders on record
- 6
- Grants received
- $53k
- Net assets
- $-3024865
What San Tan Montessori School Inc does
Mission
San Tan Charter School is a tuition-free charter school in Gilbert, Arizona, serving students from preschool through 12th grade. With Montessori, Gifted, and Mainstream programs, we provide families with educational choice and a supportive, close-knit community where every child can grow. Guided by our mission to educate the whole child, we focus on academics, social-emotional development, and strong relationships between students, families, and staff.
As stated on its FY2025 Form 990.
Program
Charter School for grades K through 12
$10,103,525 spent100% of program spending
The program described on its FY2024 Form 990. Program spending in total: $10,103,525.
The organization over time
Each line starts at 100 in 2020, so what you read is the shape rather than the size: 150 means half as much again as 2020, 50 means half. The number beside each label in the key is where it ended. The shaded band is where the middle 50% of its peers' revenue would sit, given their growth.
Balance sheet
Total assets and total liabilities at each year end, in dollars. The largest one-year move in total assets was 2022 to 2023, from $29M to $28M (−4%).
How it's funded, over time
Each bar is one year's revenue split into where it came from, and every bar is the same height — these are shares, not amounts, so a year that raised twice as much looks the same size. Hover a bar for the split.
Government-grant reliance: 2020 93% · 2021 87% · 2022 94% · 2023 23% · 2024 15% · 2025 92%. Grants only. Government contracts and fees sit inside program revenue.
93% of San Tan Montessori School Inc’s revenue is contributions — more reliant on donations than three-quarters of its peers (23% for the typical peer).
Surplus & reserves
Operating surplus or deficit each year, and months of liquidity in hand. 3 of the last 6 reported years ran a deficit.
reserve
Leadership and staff
The officers, directors, trustees and key employees listed on each return. Joined and no longer listed compare each filing with the year before, matching people by surname and first initial; a year after a gap, or a roster under three people, has no comparison.
Who funds it, year by year
2018 → 2023: the base broadened from 1 funder to 2 funders, grant income fell $7k → $6k.
3 of 6 of your funders are donor-advised or pass-through sponsors (tagged DAF) — 63% of grant dollars received. That money is really individual donors directing a sponsor; the institutions to cultivate are the non-DAF funders.
From the IRS filings of San Tan Montessori School Inc’s funders (the co-funder graph). Association, not causation. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
How concentrated its funding is
San Tan Montessori School Inc leans on a few funders — its largest provides 46% of grant income and the top three 77%; half comes from just 2 funders.
the vertical line marks half of all grant income — 2 funders to its left
81% of the income these shares are computed over arrives through pass-through sponsors or from payers whose filings do not say what kind of payment it is. Concentration is still measured over all of it, because the money is real; what it does not support is a claim about how many institutions have chosen to fund San Tan Montessori School Inc.
Largest funder’s share by year: 2018 100% · 2020 100% · 2021 100% · 2022 100% · 2023 90% — diversifying over time.
“Effective funders” = inverse Herfindahl index (1 / Σ shareᵢ²) — the number of equal-sized funders that would give the same concentration. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
Where its funders are
63% of San Tan Montessori School Inc's grant income arrives through donor-advised or pass-through sponsors, whose addresses record where the money is held rather than where the donor is. Of the $20k that is directly attributable, 74% of it comes from Arizona funders.
Funder states come from each funder’s own filing. $34k arriving through sponsors registered in 3 states is excluded from the map and the split above: a sponsor holds money on a donor’s behalf, so its registered address would place those dollars somewhere no donor need ever have been. Trends are read to FY2023, the last fiscal year that has finished arriving. FY2024–FY2026 are still being filed and are shown unshaded; they do not move any figure on this page.
Against its field
San Tan Montessori School Inc's revenue grew 25% between 2020 and 2025.
this organization peer median middle 50% of peers· 3,758 education nonprofits $10M–$100M, FY2025
Organizations like San Tan Montessori School Inc
Organizations whose mission and program text most resemble this one, by semantic similarity over every organization in the US filings — the closest peers, and often the clearest route to shared or prospective funders.
In Arizona
Nationally
Read directly from this organization’s own Form 990, as neutral context.
Where the money goes
86% of spending goes to programs.
Governance
Screen this organization
A dated, signed PDF of the compliance screen for San Tan Montessori School Inc: IRS status (Business Master File, Publication 78, auto-revocation), the OFAC sanctions lists, the Internal Revenue Bulletin, and California registration, with the Rev. Proc. 2018-32 §8.01 reliance elements stated element by element. Generated from the current files at the moment you download it.
Screens are triage, not determinations; a source that cannot be read reports not screened, never clear. Screen this nonprofit · How the screen works · on the API as GET /api/screening/{ein}?format=pdf
Questions and answers
- Who funds San Tan Montessori School Inc?
- San Tan Montessori School Inc (Arizona) receives grants from 6 organizations whose IRS filings report $53,271 to it, the largest being AMERICAN ONLINE GIVING FOUNDATION INC ($24,389). 2 of them have funded it in more than one year, and 63% of the money arrives through donor-advised or pass-through sponsors rather than from an institution directly.
- How many funders does San Tan Montessori School Inc have?
- IRS filings report 6 organizations giving $53,271 in grants to San Tan Montessori School Inc, 2 of which have funded it in more than one year.
- Who is the largest funder of San Tan Montessori School Inc?
- AMERICAN ONLINE GIVING FOUNDATION INC is the largest funder on record, with $24,389 in grants. The full list of funders is on this page.
- How can an organization like San Tan Montessori School Inc find more funders?
- Start with the funders already giving here, then look at the foundations that back similar organizations in Arizona. The funding by cause and by state pages list the largest funders for a given area and how to approach them.
Play a game about who funds San Tan Montessori School →
These figures are read directly from IRS Form 990 / 990-PF e-file XML: this organization’s own return for FY2025 (financials across 2020–2025), and the filings of 6 funders that report grants to it. “On record” means captured in the filings we have parsed — a funder that does not e-file, or whose grant detail is not itemized, will not appear. Filings run roughly 12–24 months behind. Trends on this page end at FY2023, the last fiscal year that has finished arriving; later years are shown and marked, and move no figure. Data on this page was exported October 14, 2026. What this page cannot tell you · view filing