Mariposa Elementary, Ontario CA - Test Scores & Data

Original Research by School Decision on Mariposa Elementary

Mariposa Elementary serves kindergarten through sixth grade in Ontario, a fast-growing logistics and distribution hub in San Bernardino County. The school sits in a neighborhood where the vast majority of families qualify for free or reduced-price meals, reflecting the economic profile of the surrounding community. Enrollment is small, with about a handful of students in sixth grade and stable numbers across the younger grades.

The student body is predominantly Hispanic, with smaller shares of Black, Asian, and white students. Demographic data on English learner enrollment and students with individualized education plans were not available.

Academic performance on California's state assessments shows proficiency rates below the midpoint among districts in San Bernardino County across both English language arts and mathematics. In English language arts, proficiency ranges from low in third grade to a relative high in fifth grade. Mathematics proficiency is similarly low and consistent across grades three through five; sixth-grade results were suppressed, likely due to the very small cohort. Science proficiency, measured in fifth grade only, was also low. State testing data for earlier grades is not collected. Trend data covering multiple years was not provided, so year-to-year change cannot be assessed.

The school is a regular public school, not a charter or magnet program, and serves as part of the Ontario-Montclair school district. No recent information about strategic changes or new initiatives in the district was found. The school's website was not provided in available records.

Ontario itself is undergoing rapid residential growth, driven largely by Ontario Ranch, a master-planned community to the south that will eventually include eight new schools. The historic downtown near Euclid Avenue remains the civic anchor, with walkable streets and anchors like the Ovitt Family Community Library and Ontario Town Square, though the broader city averages lower walkability and remains car-dependent. Major employers in the area span logistics, retail, manufacturing, and healthcare. Housing values in the zip code have remained relatively stable year over year, with rents moderately stable as well.

Mariposa's location in East D Street places it in the older, more established part of Ontario rather than in the fast-growing master-planned areas. A parent considering this school may want to look into current proficiency trends and any school-level supports in place to help close the academic gap reflected in these state test results.

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Academic performance

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

Math

Grade 325%

School 25% · District 40% · ▼ 16 pts below district

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

Grade 424%

School 24% · District 34% · ▼ 10 pts below district

▼ 14 pts below state median · ▼ 5 pts below county median

Grade 527%

School 27% · District 34% · ▼ 7 pts below district

▼ 4 pts below state median · ▲ 5 pts above county median

English language arts

Grade 321%

School 21% · District 37% · ▼ 16 pts below district

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

Grade 427%

School 27% · District 40% · ▼ 13 pts below district

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

Grade 537%

School 37% · District 47% · ▼ 10 pts below district

▼ 8 pts below state median · ▼ 3 pts below county median

Science

Grade 519%

School 19% · District 25% · ▼ 7 pts below district

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

This schoolOntario-Montclair, 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.