Enrollment
378
High
STATE 834
SCHOOL COMMUNITY·SENECA TWP HSD 160·NCES 173585003728
Seneca High School
307 E Scott St, Seneca, IL 61360 · (815) 357-5000 · LaSalle County
GRADES 09–12HIGH42-RURALREGULAR SCHOOL378 STUDENTS
Student : Teacher
9.9:1
38 FTE teachers
STATE 13.8:1
Free / Reduced Lunch
31%
119 students
STATE 56%
Community
0
0 members
Enrollment and student:teacher ratio compared against other high schools. Free/Reduced Lunch and demographics compared against all schools.
Enrollment by grade, 2024-25
| Grade | Students | Share |
|---|---|---|
| Grade 9 | 100 | 26% |
| Grade 10 | 95 | 25% |
| Grade 11 | 90 | 24% |
| Grade 12 | 93 | 25% |
Student demographics
27%Diversity index
The chance that two students picked at random belong to different racial or ethnic groups.
STATE 69% · US 70%
Student head counts by race/ethnicity from federal NCES enrollment data. District, state, and US figures are each group's share of all public school students in that area (US excludes territories). Very small groups may be suppressed in the source, so categories do not always sum exactly to total enrollment.
Gender split
BeatsExpectations
Demographically-adjusted score · methodologyTier
UNDERPERFORMING
Bottom 10% of IL schools after controlling for student poverty
Actual proficiency
38.5%
composite math + reading, all grades
Predicted
53.3%
based on IL schools with similar FRL share
Beats by
-14.8pp
below demographic expectation
What this means: About 39% of students here test proficient in math and reading, below the roughly 53% typical for Illinois schools with a similar share of low-income students. BeatsExpectations compares each school with others at the same poverty level, not by raw scores, so a school lands here when its results trail those comparable schools, which is not the same as having low scores. A higher-scoring school can still fall in this tier if similar schools score higher still.
BeatsExpectations runs a per-state regression of proficiency on free/reduced-lunch share, then scores each school by residual. How this is calculated →
Schools most like Seneca High School
Seneca High School's state test result (38.5% proficient) is higher than 1 of the 5 schools below with a result.
| School | Students | Low-income | Proficient |
|---|---|---|---|
| Seneca High School this school | 378 | 31.5% | 38.5% |
| Stillman Valley High School Stillman Valley | 433 | 30.3% | 46.6% |
| Johnsburg High School Johnsburg | 502 | 32.1% | 44.3% |
| Wesclin Sr High School Trenton | 343 | 33.5% | 44.5% |
| El Paso-Gridley High School El Paso | 364 | 33.2% | 57.6% |
| Morrison High School Morrison | 294 | 34.4% | 37.9% |
Matched among Illinois high schools on enrollment, the share of students from low-income families (eligible for free or reduced-price lunch), and racial and ethnic makeup. Proficient is the average share of students meeting the state standard across all of the school's state tests in 2023-24 and 2024-25, the same combined score our test-score rankings use. Online schools and schools serving specialized populations are not matched.
Where Seneca High School ranks
Among high schools| Measure | This school | In Illinois | In LaSalle County |
|---|---|---|---|
| State test proficiency ranked highest first | 38.5% | #216 of 573 | N/A |
| Enrollment ranked largest first | 378 | #391 of 708 | #5 of 8 |
| Students per teacher ranked fewest first | 9.9:1 | #17 of 528 | N/A |
| Diversity index ranked most diverse first | 26.7% | #321 of 537 | N/A |
| Free and reduced lunch ranked highest share first | 31.5% | #494 of 578 | N/A |
| Enrollment change since 2017-18 ranked steepest decline first | -17.1% | #78 of 358 | #2 of 6 |
Ranked against other public high schools. Online schools are left out of every list, and test-score lists leave out schools that serve specialized populations. Each rank links to the full list. Arrows under a test-score rank show places moved since the prior test year, among schools tested both years.
4-year change
SY 2020-21 vs SY 2024-25Enrollment
378
-25 (-6%) vs 2020
-4% since 1990-91, when it was 395
Source: NCES Common Core of Data
Enrollment and staffing by year
| School year | Students | Teachers (FTE) | Students per teacher | Free and reduced lunch |
|---|---|---|---|---|
| 2024-25 | 378 | 38 | 9.9:1 | 31% (119) |
| 2023-24 | 361 | 36 | 10.0:1 | 35% (126) |
| 2022-23 | 385 | 38 | 10.1:1 | 33% (128) |
| 2020-21 | 403 | N/A | N/A | N/A |
| 2017-18 | 456 | 36.5 | 12.5:1 | 30% (139) |
| 2015-16 | 445 | 38 | 11.7:1 | 24% (105) |
| 2010-11 | 446 | 27 | 16.5:1 | 19% (85) |
| 2000-01 | 490 | 43 | 11.4:1 | N/A |
| 1990-91 | 395 | 41 | 9.6:1 | N/A |
Source: NCES Common Core of Data. Rows are the federal collections on file for Seneca High School.
Since 2017-18: students down 17% (456 to 378); teachers up 4% (36.5 to 38).
About Seneca High School
This page covers Seneca High School, a small high school in Seneca, Illinois. It had 378 students in 2024-25, spanning grades 9 through 12. That compares with an average of about 834 students for high schools in Illinois.
Seneca Twp HSD 160 is the district for Seneca High School.
At Seneca High School, 85% of students are White. Other students are 12% Hispanic and 3% multiracial. Census estimates put LaSalle County at about 86% White, close to the school's figure. Measured by the diversity index, the student body scores 27%.
For every teacher at Seneca High School, there are about 9.9 students; the school has 38 full-time-equivalent teachers. The average for high schools in Illinois, 13.8:1, is higher. There are 119 students eligible for free or reduced-price lunch, 31% of enrollment. It compares with 53% for public schools in LaSalle County.
Seneca High School is 14.8 points below expectations on state tests, given its student poverty level, placing it in the bottom 10% in Illinois.
In the wider LaSalle County area, the median household earns about $73,045 a year, a bachelor's degree or higher is held by about 21% of adults, and the share of residents below the poverty line is 11%. LaSalle County counts 54 public schools with about 14,523 students.
About 0.5 miles separate Seneca High School from the closest public school, Seneca Grade School North Campus. Within five miles are 3 other public schools. The average proficiency across nearby scored schools is 45.7%; Seneca High School's is 38.5%, ranking 6th of 8.
By NCES locale, the school is Rural: Distant, or in rural territory some distance from an urban area.
Enrollment decreased 6% over 4 years, reaching 378 in 2024-25.
You can use this page to share news and ask questions about athletics, class schedules, and weather closures. Current and former families are welcome to add their experience.
LaSalle County at a glance
View full county profilePopulation
108,714
Census ACS
Median income
$73,045
Household, ACS
Bachelor's+
21%
Adults 25+
Poverty rate
11%
Below federal line
Schools in county
54
14,523 students
Quick facts
Related schools
Other schools in Seneca
- Seneca Grade School North CampusElementary · 256 students
- Seneca Elementary School South CampusMiddle · 209 students
Other Seneca High schools
6 other US public schools in 7 states are named Seneca High. Seneca High School is the 6th largest of the 7.
- Seneca HighLouisville, KY · 1,255 students
- Seneca High SchoolTABERNACLE, NJ · 1,058 students
- Seneca HighSeneca, SC · 1,051 students
- SENECA HIGHSENECA, MO · 450 students
- Seneca High SchoolErie, PA · 383 students
Nearby schools
- Seneca Grade School North Campus0.5 mi · 256
- Seneca Elementary School South Campus0.5 mi · 209
- Marseilles Elementary School4.9 mi · 528
- Milton Pope Elementary School5.9 mi · 195
- Nettle Creek Elementary School8.1 mi · 77
- White Oak Elementary8.5 mi · 722
Frequently asked questions
About Seneca High SchoolHow large is Seneca High School?
Seneca High School enrolls approximately 378 students in grades 09-12.
What age range does Seneca High School serve?
Seneca High School serves students from grade 09 through grade 12.
How many students per teacher at Seneca High School?
Approximately 9.9:1 students per teacher at Seneca High School.
What is the racial breakdown of students at Seneca High School?
At Seneca High School, the student body is approximately 85% White, 12% Hispanic, 0% Asian, 3% Two or more.
Who oversees Seneca High School?
Seneca High School is overseen by Seneca Twp HSD 160 in LaSalle County.
Data sourceSchool profile facts are sourced from the NCES. Community content is posted by allk12 members.