Seaford Harbor School, Seaford NY

Original Research by School Decision on Seaford Harbor School

Seaford Harbor School serves kindergarten through fifth grade in a small, suburban setting on Long Island. It enrolls a student body that is predominantly white, with smaller shares of Hispanic, Asian, and multiracial students. Just under a tenth of students qualify for free or reduced-price lunch, placing the school in a relatively affluent household context. The school sits in the Seaford Union Free School District, which has held budgets at or below New York State's tax levy cap in recent years, a choice that provides some property-tax predictability for families in the area.

State testing data from the 2024-2025 school year shows mixed academic results across the grades the school serves. In math, students reach proficiency at higher rates in third grade than in the upper elementary years. By fourth and fifth grade, math proficiency drops noticeably, with fewer than three-quarters of students performing at proficient levels. Reading and language arts show a steeper decline in fourth grade before recovering in fifth. Science proficiency at the fifth-grade level falls below half. These patterns suggest the school may benefit from looking into why students struggle with academic growth in the fourth-grade year and in science. A parent may want to ask the school directly about supports in place for these shifts and about any interventions the school has introduced to address them.

Overall proficiency across tested subjects and grades sits above the midpoint when compared to other elementary schools in Nassau County, which is a strength. The school's average performance reflects solid work in early elementary math, though that advantage narrows in the upper grades served.

Seaford itself is a well-established residential community about half an hour east of Manhattan, defined by single-family homes, canal-front neighborhoods, and small commercial corridors along its main roads. The Babylon Branch of the Long Island Rail Road serves the hamlet, offering commuter rail access to the city, and parks including Seamans Neck and Cedar Creek provide recreation nearby. The housing market in the zip code has climbed in value; homes have been appreciating steadily, and the market remains tight. New construction tends to be scattered infill and tear-down rebuilds rather than large developments.

The district recently made two meaningful additions for families: it launched a free, lottery-based universal pre-K program after earlier deciding against it, and it expanded college-credit course offerings at the high school through a partnership with Long Island University while adding technology for coding instruction in elementary grades. These changes suggest the district is responsive to community needs and investing in pathways beyond traditional academics.

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Academic performance

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

Math

Grade 386%

School 86% · District 79% · ▲ 7 pts above district

▲ 27 pts above state median · ▲ 11 pts above county median

Grade 476%

School 76% · District 74% · ▲ 3 pts above district

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

Grade 574%

School 74% · District 81% · ▼ 7 pts below district

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

English language arts

Grade 368%

School 68% · District 73% · ▼ 4 pts below district

▲ 16 pts above state median · ▲ 1 pts above county median

Grade 446%

School 46% · District 58% · ▼ 12 pts below district

▼ 7 pts below state median · ▼ 22 pts below county median

Grade 577%

School 77% · District 83% · ▼ 6 pts below district

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

Science

Grade 548%

School 48% · District 59% · ▼ 11 pts below district

▲ 6 pts above state median · ▼ 13 pts below county median

Social studies

Grade 598%

School 98% · district not reported

▲ 6 pts above state median · even with county median

This schoolSEAFORD UNION FREE SCHOOL DISTRICT, 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.

Proficiency by household income

English language arts

Grade 3Lower-income20%Higher-income73%53 pp gap

Grade 4Lower-income20%Higher-income49%29 pp gap

Grade 5Lower-income67%Higher-income79%12 pp gap

Mathematics

Grade 4Lower-income60%Higher-income78%18 pp gap

Grade 5Lower-income50%Higher-income77%27 pp gap