ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL

ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL is a medium-sized 9-12 campus in MOUNT SINAI, New York, run under MOUNT SINAI UNION FREE SCHOOL DISTRICT. The school serves 710 students in grades 9 through 12.

Within MOUNT SINAI UNION FREE SCHOOL DISTRICT, which oversees 3 schools and 1,984 students, ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL is one campus in the system.

On the student-mix side, ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL lists that the largest single group is White, at 74% of enrollment; the rest is composed of 14% Hispanic, 9% Asian. The wider county runs roughly 66% White, putting the school's mix considerably more White than the area baseline.

Looking at the economic backdrop, The school currently runs with 65 full-time-equivalent teachers, for a student-teacher ratio near 10.9:1. The state averages about 11.0:1, putting this campus right in line with peers. An estimated 12% of students are eligible for free or reduced-price lunch, a commonly cited indicator of low-income enrollment. Set against Suffolk County (around 39%), the school's rate is south of typical.

With demographic context factored in, ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL sits in the top 10% of New York schools after the BeatsExpectations adjustment. Predicted proficiency for the school's FRL share is roughly 70.5%; actual is 95.5%, +25.0 points clear of the demographic baseline.

Across the wider county, census data for Suffolk County shows median household income runs about $130,686, roughly 40% of adults have completed at least a four-year degree, and the poverty rate sits near 4%. In all, Suffolk County runs 343 public schools (combined enrollment of about 222,439 students), of which ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL is one.

The closest other public school is MOUNT SINAI MIDDLE SCHOOL, roughly 0.2 miles away. Within five miles, there are 8 other public schools. Among the 9 schools in that immediate cluster with test data (this one included), ROBERT M GRABLE JR MOUNT SINAI HIGH SCHOOL ranks 1st on composite proficiency, higher than the local average of 68.0%.

Geographically, the school is in an outer-ring area.

Trend over the last 7 years. Over the past 7-year window, the student count edged down 9%: 782 students in 2018 compared to 710 in 2025. The White share of enrollment edged down from 84% to 74% over that span. The student-to-teacher ratio pulled in from 13.8:1 in 2018 to 10.9:1 today.

On the community side, recent activity here tends to focus on enrollment questions, classroom assignments, and PTA news. The community welcomes input from current and former families.