Compiled from official source data by PlainSchools.
7 public K-12 schools in Central Islip from NCES Common Core of Data: enrollment, grade span, demographics, and Civil Rights Data Collection statistics for every active campus.
According to NCES CCD 2024-25, Central Islip has more public-school enrollment than 69% of the 4,487 US cities in this directory. Central Islip Senior High School enrolls 37.6% of Central Islip's public-school students. That is enough concentration for one institution to pull the citywide enrollment, staffing, and Resource Index averages toward its own profile. The smaller campuses below should therefore be compared directly rather than inferred from the headline mean; their grade configurations and program footprints can be materially different even inside the same district.
The school portfolio is elementary-weighted
4 of Central Islip's 7 listed schools are elementary campuses. That composition means citywide enrollment and staffing averages are influenced more by early-grade operating patterns than by the city's 1 middle and 1 high-school records. Families comparing later grades should rely on those individual rows rather than the all-school mean.
The composite and staffing measures point in different directions
Central Islip's average Resource Investment Index sits at the 7th percentile, while its teacher-staffing measure sits at the 58th percentile. The 51-point percentile gap is a reminder that the index is not a class-size score: counselors, gifted-program reporting, and attendance also affect it. Compare those components directly when two schools have similar index totals; the same headline score can arise from a different mix of reported resources.
City enrollment
Top 31%
School count
Top 65%
Resource Index average
7th percentile
Teacher staffing
58th percentile
Central Islip Senior High School accounts for 37.6% of all Central Islip public-school enrollment
That dominant concentration means Central Islip-wide averages can mask substantial variation outside the largest entity. Grade level: High. The share measures enrollment concentration only; it does not establish how districts allocate programs, capital, or staff. Enrollment-weighted aggregates give this entity more weight than any smaller peer, while an unweighted entity average treats every record equally.
Central Islip school enrollment varies 5.3× across entities
Central Islip school enrollment ranges from 490 students (lowest) to 2,615 students (highest), a spread of 2,125 students. That relatively narrow ratio reflects an unusually homogeneous school portfolio for a city this size. Per-school staffing and program breadth can differ sharply at opposite ends of that enrollment range, so the city average should not be treated as a typical campus.
Central Islip reports 75.1% free-lunch eligibility
The reported share is at least 75%, indicating a high concentration of measured economic need. Title I operates under the Every Student Succeeds Act (ESSA, 2015), but its statutory allocation uses additional LEA-level counts and rules not represented by this average. This percentage is an economic-need context measure; it does not establish a Title I award, show dollars received, or describe how funds are distributed among campuses.
Central Islip operates one school district — a single-district system
Central Islip's listed schools share one district boundary, budget authority, and reporting chain. That makes citywide and districtwide governance easier to compare, but it does not make individual campuses uniform: grade configuration, staffing, programs, and student need can still vary materially within the same school district.
Central Islip student-teacher ratio is 14.7:1 — near the typical range (US average ~15.7) — citywide staffing is neither unusually lean nor unusually crowded by this measure
student-teacher ratio is the simplest comparative metric but it does not capture the full picture: the ratio counts FTE classroom teachers against total enrollment, push-in specialists, English-language aides, special-education co-teachers, and counselors are not included in most reporting Variation between sub-units within Central Islip is typically wider than the Central Islip-aggregate figure suggests.
Most racially and ethnically mixed schools in Central Islip
Ranked by the Simpson student-body diversity index (0-100) from NCES race and ethnicity data, where higher means a more evenly mixed student body. It measures mix, not quality.
What do families ask about schools in Central Islip?
Which Central Islip school has the highest Resource Investment Index? ▼
Central Islip Senior High School has the highest Resource Investment Index among the Central Islip schools in this federal-data comparison at 41/100. The index summarizes reported staffing, counseling, gifted-program, and attendance inputs; it is not an academic rating.
How many schools are in Central Islip, NY? ▼
Central Islip has 7 public schools with a total enrollment of 6,952 students. Average student-teacher ratio: 14.7:1.
Data from NCES Common Core of Data (CCD) 2024-25 and Civil Rights Data Collection (CRDC) 2021-22. The Resource Investment Index uses reported student-teacher ratio,
counselor access, gifted programs, and attendance; it is not an academic rating. Cities must include at least five schools to be listed. This public-data comparison is for informational purposes:
verify current enrollment, attendance boundaries, and programs with the school district before acting. See the guide to understanding NCES data.
