Isthmus Montessori Academy Public, Madison WI

Original Research by School Decision on Isthmus Montessori Academy Public

Isthmus Montessori Academy Public is a small public charter school in Madison that serves students from prekindergarten through twelfth grade under the Montessori model. It operates as its own district, Isthmus Montessori Academy Inc., and is the city’s only public International Baccalaureate school, having earned IB World School status for the Diploma Programme in 2021. For families seeking a Montessori approach within a public school, and one that leads into an internationally recognized high school curriculum, this is a distinctive option in Dane County.

The school’s enrollment is small and its student body is predominantly white, with the largest minority groups being Hispanic and students identifying as two or more races. A very small share of students qualify for free or reduced-price lunch, indicating a relatively low level of economic disadvantage among the families served. Data on special education and English learner populations were not reported, so those dimensions of student support are not possible to characterize here.

State assessment results from the Wisconsin Forward exam for the 2024-25 school year provide a mixed but instructive picture. In math, proficiency rates in the early grades—third through fifth—fell roughly in the middle of the range, with around two in five students meeting the standard. A sharper rise appeared in sixth grade, where a clear majority of students were proficient, and seventh grade continued at a strong level, though eighth grade dropped back to a rate similar to the earlier grades. In English language arts, third graders were the weakest performing group, with roughly one in five reaching proficiency, but the trajectory improved steadily through fourth, fifth, and sixth grades, and by seventh and eighth grades a large majority of students were proficient. Science and social studies, tested only in fourth and eighth grades, showed high levels of proficiency at both points. Overall, the school’s composite proficiency across all tested subjects stood above the midpoint relative to other districts in Dane County, a notable position given that it operates as a single-school district.

Because the school serves high school grades but had no graduation rate reported, and state testing data for grades nine through twelve were not available in this dataset, it is not possible to evaluate high school outcomes from state measures. A parent considering the upper grades would want to learn directly from the school about its college and career preparation record, especially given the IB Diploma Programme offering.

Located on Madison’s east side, the school draws from the broader city, which is a fast-growing state capital and university town with a progressive identity, lakefront setting, and a knowledge-based economy anchored by the University of Wisconsin–Madison, state government, and major employers like Epic Systems and UW Health. Housing values in the immediate area are above the national average and have been rising modestly, while rents have also increased slightly. The city is known for its bike paths, parks, and walkable downtown, but the school’s neighborhood is more residential and car-dependent.

For families who value Montessori pedagogy and want a public school option that avoids the cost of private Montessori programs, Isthmus Montessori Academy Public offers a rare alignment. The early elementary results in reading suggest room for growth, and a parent should ask what supports are in place for students who enter below grade level. The middle grades show stronger performance, and the IB framework gives a clear academic pathway through high school, though with a very small upper-grade enrollment, the high school experience will be in an intimate setting.

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Academic performance

How students perform on state tests, by grade, set against the district.

Math

Grade 344%

School 44% · District 44%

▼ 13 pts below state median · ▼ 15 pts below county median

Grade 446%

School 46% · District 46%

▼ 8 pts below state median · ▼ 11 pts below county median

Grade 548%

School 48% · District 48%

▼ 4 pts below state median · ▼ 9 pts below county median

Grade 680%

School 80% · District 80%

▲ 26 pts above state median · ▲ 21 pts above county median

Grade 764%

School 64% · District 64%

▲ 10 pts above state median · ▲ 2 pts above county median

Grade 843%

School 43% · District 43%

▼ 8 pts below state median · ▼ 11 pts below county median

English language arts

Grade 322%

School 22% · District 22%

▼ 31 pts below state median · ▼ 38 pts below county median

Grade 443%

School 43% · District 43%

▼ 9 pts below state median · ▼ 14 pts below county median

Grade 552%

School 52% · District 52%

▲ 2 pts above state median · ▼ 1 pts below county median

Grade 660%

School 60% · District 60%

▲ 7 pts above state median · ▲ 2 pts above county median

Grade 782%

School 82% · District 82%

▲ 30 pts above state median · ▲ 25 pts above county median

Grade 879%

School 79% · District 79%

▲ 26 pts above state median · ▲ 20 pts above county median

Science

Grade 471%

School 71% · District 71%

▲ 20 pts above state median · ▲ 15 pts above county median

Grade 885%

School 85% · District 85%

▲ 33 pts above state median · ▲ 32 pts above county median

Social studies

Grade 479%

School 79% · District 79%

▲ 14 pts above state median · ▲ 9 pts above county median

Grade 885%

School 85% · District 85%

▲ 20 pts above state median · ▲ 16 pts above county median

This schoolIsthmus Montessori Academy Inc, same grade

Graduation rate (ACGR) reflects the federally published Adjusted Cohort Graduation Rate for the most recent year available. We refresh this data annually at the close of each academic year in June. The federal source publishes a banded rate (for example, "90-94%") instead of an exact number for cohorts small enough to risk identifying individual students. The state distribution chart, where shown, plots every school in the state with a published rate or band; schools whose rate is federally suppressed are excluded. Where the federal source publishes a band rather than an exact rate, the school is placed within its band using a stable, ID-derived offset, so its position is consistent across visits.