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SCHOOL COMMUNITY·ST. MARY'S COUNTY PUBLIC SCHOOLS·NCES 240060001224

Great Mills High

21130 Great Mills Rd, Great Mills, MD 20634 · (301) 863-4001 · St. Mary's County
GRADES 09–12HIGH23-SUBURBTITLE IREGULAR SCHOOL1,697 STUDENTS
Enrollment
1,697
High
DISTRICT 1,780 · STATE 1,185
Student : Teacher
19.1:1
89 FTE teachers
DISTRICT 20.2:1 · STATE 15.3:1
Free / Reduced Lunch
57%
975 students
DISTRICT 43% · STATE 54%
Community
2
0 members
Enrollment and student:teacher ratio compared against other high schools. Free/Reduced Lunch and demographics compared against all schools.
Enrollment by grade
Grade 9
481
Grade 10
435
Grade 11
392
Grade 12
389
Student demographics
White
58434%
DISTRICT 59% · STATE 31%
Hispanic
23714%
DISTRICT 10% · STATE 24%
Black
64238%
DISTRICT 19% · STATE 32%
Asian
503%
DISTRICT 2% · STATE 7%
Two+
17410%
DISTRICT 9% · STATE 5%
Native American
80%
DISTRICT 0% · STATE 0%
Pacific Islander
20%
DISTRICT 0% · STATE 0%
Student head counts by race/ethnicity from federal NCES enrollment data. Very small groups may be suppressed in the source, so categories do not always sum exactly to total enrollment.
Gender split
Male
87852%
Female
81948%

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Test scores

MCAP 2024-25 . % Proficient (Levels 3-4)
English Language Arts
55.9%
MD avg 50.6% . +5.5pp since 2023
Math
12.2%
MD avg 34.8% . +2.2pp since 2023

What this means: On the MCAP, Maryland's statewide test, about 56 of every 100 students at this school read and write at grade level and about 12 of 100 do math at grade level. Across all Maryland schools, those numbers are about 51 and 35. Reading and writing scores are up about 6 points since 2023, while math scores are up about 2 points.

Source: MCAP. All students, all grades. See all years and grades →

BeatsExpectations

Demographically-adjusted score · methodology
Tier
AS EXPECTED
Performing as predicted given the school's student profile
Actual proficiency
32.1%
composite math + reading, all grades
Predicted
40.2%
based on MD schools with similar FRL share
Beats by
-8.1pp
below demographic expectation

What this means: About 32% of students here test proficient in math and reading, compared with the roughly 40% typical for Maryland schools with a similar share of low-income students. BeatsExpectations measures results against demographically similar schools rather than by raw scores, and this school falls within the typical range, neither among Maryland's top nor bottom 10%.

BeatsExpectations runs a per-state regression of proficiency on free/reduced-lunch share, then scores each school by residual. How this is calculated →

7-year change

SY 2017-18 vs SY 2024-25
Enrollment
1,697
+42 (+3%) vs 2017
Student : Teacher
19.1:1
was 19.4:1
% White
34%
was 41%
% Hispanic
14%
was 11%
% Black
38%
was 37%
% Asian
3%
was 5%
Source: NCES Common Core of Data

About Great Mills High

As a mid-tier senior high in Great Mills, Maryland, Great Mills High teaches 1,697 students from grades 9 through 12, part of St. Mary's County Public Schools. Enrollment runs roughly 43% bigger than the state mean of about 1,185.

Across the 26 schools in St. Mary's County Public Schools (16,905 students total), Great Mills High accounts for its share of the district's footprint.

Demographically, Great Mills High reports that the most-represented group is Black (38%), with the rest of the student body spread across multiple groups. The remainder is composed of 34% White, 14% Hispanic, 10% multiracial, 3% Asian. By comparison, St. Mary's County as a whole is about 15% Black, so the school skews meaningfully more Black than its surroundings.

On the income-and-resources front, Great Mills High logs 89 full-time-equivalent teachers, putting the student-to-teacher ratio at about 19.1:1. The state averages around 15.3:1, so this campus is higher than the state norm typical. An estimated 57% of students are eligible for free or reduced-price lunch, a number frequently used as a low-income enrollment indicator. By comparison, St. Mary's County runs at roughly 41%, so the school's eligibility rate is meaningfully above the surrounding baseline.

After controlling for student poverty, Great Mills High tracks the demographic baseline. The model predicts 40.2% given the school's FRL share; actual proficiency is 32.1%.

Around the school, community-level numbers for St. Mary's County indicate median household earnings sit near $119,446, about 37% of the adult population holds a bachelor's degree or above, and roughly 6% of residents live below the federal poverty line. Across St. Mary's County's 28 public schools (combined enrollment of about 16,905 students), Great Mills High is one campus in the mix.

The closest other public school is George Washington Carver Elementary, roughly 0.4 miles away. Within five miles, there are 8 other public schools. Ranking that nearby cluster on reported proficiency puts Great Mills High at 8th of 9; the average score across the group is 43.9%.

Great Mills High operates from a residential location.

Looking at the recent track record. Great Mills High's enrollment has edged up 3% since 2018, when it stood at 1,655 (now 1,697). White enrollment moved from 41% to 34% across the same window.

On allk12, the feed for Great Mills High typically covers school events, parent volunteer needs, and clubs. Members of the school community can share what they know.

St. Mary's County at a glance

View full county profile
Population
115,126
Census ACS
Median income
$119,446
Household, ACS
Bachelor's+
37%
Adults 25+
Poverty rate
6%
Below federal line
Schools in county
28
16,905 students

Quick facts

School name
Great Mills High
District
St. Mary's County Public Schools
Address
21130 Great Mills Rd, Great Mills, MD 20634
Phone
(301) 863-4001
County
St. Mary's County
Level
High
Grade range
09–12
Total enrollment
1,697
Teachers (FTE)
89
Student–teacher ratio
19.1:1
Free/Reduced lunch
975 (57%)
Locale
23-Suburb: Small
NCES ID
240060001224
Charter school
No
Virtual school
No

Related schools

Other schools in St. Mary's County Public Schools
Other schools in Great Mills
Nearby schools

Frequently asked questions

About Great Mills High
What is the total enrollment at Great Mills High?
Great Mills High enrolls approximately 1,697 students in grades 09-12.
What age range does Great Mills High serve?
Great Mills High serves students from grade 09 through grade 12.
What is the student-teacher ratio at Great Mills High?
The student-to-teacher ratio at Great Mills High is approximately 19.1:1 (89 FTE teachers).
How diverse is Great Mills High?
Great Mills High reports a student body of 34% White, 14% Hispanic, 38% Black, 3% Asian, 10% Two or more.
What district is Great Mills High in?
Great Mills High is part of St. Mary's County Public Schools.
Data sourceSchool profile facts are sourced from the NCES. Community content is posted by allk12 members.
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