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What advice would you give to incoming students at Mills High?
Community prompt from u/allk12. Replies below.
Enrollment
1,115
High
DISTRICT 1,092 · STATE 838
SCHOOL COMMUNITY·SAN MATEO UNION HIGH·NCES 063498005924
Mills High
400 Murchison Dr., Millbrae, CA 94030 · (650) 558-2599 · San Mateo County
GRADES 09–12HIGH21-SUBURBREGULAR SCHOOL1,115 STUDENTS
B+
allk12 Grade
Scored higher than 74% of California public high schools
- ATest scores Share of students meeting the state standard in reading, math, and other tested subjects, 2023-24 and 2024-25.
- BBeats expectations How far test scores land above or below what the share of low-income students predicts for a school in this state.
- DThree-year trend Change in reading and math proficiency over the last three test years.
Grades compare a school only with schools in the same state, because every state gives its own test. How grades work · Top-graded California public high schools
Student : Teacher
20.5:1
54 FTE teachers
DISTRICT 18.0:1 · STATE 18.2:1
Free / Reduced Lunch
20%
226 students
DISTRICT 35% · STATE 65%
Community
6
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 | 274 | 25% |
| Grade 10 | 278 | 25% |
| Grade 11 | 288 | 26% |
| Grade 12 | 275 | 25% |
Student demographics
59%Diversity index
The chance that two students picked at random belong to different racial or ethnic groups.
DISTRICT 72% · STATE 62% · 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
Test scores
CAASPP 2024-25 . % met or exceeded standardEnglish Language Arts
81.8%
CA avg 49.1% . -3.2pp since 2014
Math
63.3%
CA avg 37.7% . -8.7pp since 2014
What this means: On the CAASPP, California's statewide test, about 82 of every 100 students at this school read and write at grade level and about 63 of 100 do math at grade level. Across all California schools, those numbers are about 49 and 38. Reading and writing scores are down about 3 points since 2014, while math scores are down about 9 points.
Performance levels, 2024-25
| Subject | Standard Exceeded | Standard Met | Standard Nearly Met | Standard Not Met |
|---|---|---|---|---|
| English Language Arts | 51.5% | 30.4% | 10.0% | 8.2% |
| Math | 39.3% | 24.1% | 18.1% | 18.5% |
Share of tested students at each CAASPP level. Each student counts in one level, so a row adds to about 100%.
CAASPP results by year
| School year | English Language Arts | Math |
|---|---|---|
| 2024-25 | 81.8% | 63.3% |
| 2023-24 | 75.3% | 56.5% |
| 2022-23 | 72.8% | 56.5% |
| 2021-22 | 83.5% | 71.1% |
| 2018-19 | 75.3% | 66.3% |
| 2017-18 | 77.0% | 70.2% |
| 2016-17 | 90.5% | 74.8% |
| 2015-16 | 87.0% | 71.0% |
| 2014-15 | 85.0% | 72.0% |
% met or exceeded standard, all students and all tested grades.
Source: CAASPP. All students, all grades. See all years and grades →
BeatsExpectations
Demographically-adjusted score · methodologyTier
AS EXPECTED
Performing as predicted given the school's student profile
Actual proficiency
69.2%
composite math + reading, all grades
Predicted
67.7%
based on CA schools with similar FRL share
Beats by
+1.6pp
above demographic expectation
What this means: About 69% of students here test proficient in math and reading, compared with the roughly 68% typical for California 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 California'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 →
Schools most like Mills High
Mills High's state test result (69.2% proficient) is higher than 2 of the 5 schools below with a result.
| School | Students | Low-income | Proficient |
|---|---|---|---|
| Mills High this school | 1,115 | 20.3% | 69.2% |
| Irvine High Irvine | 1,964 | 22.6% | 66.8% |
| Walnut High Walnut | 2,148 | 23.6% | 70.7% |
| San Marino High San Marino | 886 | 11.5% | 86.0% |
| Northwood High Irvine | 2,244 | 18.8% | 72.3% |
| Piedmont Hills High San Jose | 1,918 | 30.1% | 64.9% |
Matched among California 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 Mills High ranks
Among high schools| Measure | This school | In California | In San Mateo County |
|---|---|---|---|
| State test proficiency ranked highest first | 69.2% | #85 of 1,052 | #3 of 17 |
| Math proficiency ranked highest first | 63.3% | #65 of 1,056 ▲ 35 | #3 of 17 ▲ 1 |
| Reading proficiency ranked highest first | 81.8% | #81 of 1,056 ▲ 69 | #3 of 17 ▲ 1 |
| 3-year test score change ranked biggest drop first | -4.7pp | #141 of 1,044 | #4 of 17 |
| Enrollment ranked largest first | 1,115 | #724 of 2,093 | #11 of 35 |
| Students per teacher ranked fewest first | 20.5:1 | #621 of 1,352 | #20 of 23 |
| Diversity index ranked most diverse first | 59.4% | #424 of 1,351 | #13 of 23 |
| Free and reduced lunch ranked highest share first | 20.3% | #1,487 of 1,575 | #22 of 28 |
| Enrollment change since 2017-18 ranked steepest decline first | -8.6% | #507 of 802 | #11 of 14 |
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
1,115
-65 (-6%) vs 2020
-15% since 1990-91, when it was 1,306
Student : Teacher
20.5:1
was 21.4:1
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 | 1,115 | 54.4 | 20.5:1 | 20% (226) |
| 2023-24 | 1,119 | 57 | 19.6:1 | 17% (191) |
| 2022-23 | 1,141 | 53.5 | 21.4:1 | 19% (214) |
| 2020-21 | 1,180 | 55 | 21.4:1 | 21% (244) |
| 2017-18 | 1,220 | 59.4 | 20.6:1 | 22% (272) |
| 2015-16 | 1,198 | 56 | 21.4:1 | 14% (171) |
| 2010-11 | 1,413 | N/A | N/A | 11% (152) |
| 2000-01 | 1,454 | 63 | 23.1:1 | 2% (24) |
| 1990-91 | 1,306 | 55 | 23.8:1 | N/A |
Source: NCES Common Core of Data. Rows are the federal collections on file for Mills High.
Since 2017-18: students down 9% (1,220 to 1,115); teachers down 8% (59.4 to 54.4).
About Mills High
Students in Millbrae, California, attend Mills High, a medium-sized high school. The student body numbers 1,115 students, from grades 9 through 12. Average enrollment for high schools in California is about 838, so this school runs 33% bigger than that.
San Mateo Union High oversees Mills High and 7 other schools, with 8,736 students in total.
A majority of students at Mills High, 59%, are Asian. Other reported shares: 20% Hispanic, 11% White, and 9% multiracial. San Mateo County's residents are about 31% Asian, 27 points below the school's share. Mills High has a diversity index of 59%, compared with 70% for all US public school students.
Federal data list 54.4 full-time-equivalent teachers at Mills High in 2024-25, for a ratio of 20.5:1. The average ratio among high schools in California is 18.2:1, lower than at this school. The school's rate of free or reduced-price lunch eligibility is 20%. It compares with 34% for public schools in San Mateo County.
Mills High is graded B+ by allk12, scoring above 74% of California public high schools once test results, poverty-adjusted performance, and the recent trend are combined.
Mills High is 1.6 points above its predicted average proficiency rate on state tests (69.2% versus 67.7%), which places it in neither the top nor the bottom 10% in California.
According to the American Community Survey, in San Mateo County, median household income is about $158,855, a bachelor's degree or higher is held by about 54% of adults, and the share of residents below the poverty line is 4%. Mills High is one of 176 public schools in San Mateo County, which together enroll about 82,403 students.
The closest public school to Mills High is Spring Valley Elementary, about 0.2 miles away. Other public schools within five miles number at least 8. Nearby schools with test data average 75.6% proficiency; Mills High posts 69.2%.
On the NCES locale scale, the school is Suburb: Large.
A comparison of 2020-21 and 2024-25 shows enrollment down 6%, from 1,180 to 1,115.
Community posts for Mills High can cover sports schedules, lunch menus, and spirit week. Alumni can share how the school prepared them.
San Mateo County at a glance
View full county profilePopulation
742,340
Census ACS
Median income
$158,855
Household, ACS
Bachelor's+
54%
Adults 25+
Poverty rate
4%
Below federal line
Schools in county
176
82,403 students
Quick facts
Related schools
Other schools in San Mateo Union High
- Aragon HighHigh · 1,658 students
- Hillsdale HighHigh · 1,585 students
- Burlingame HighHigh · 1,583 students
- San Mateo HighHigh · 1,557 students
- Capuchino HighHigh · 1,061 students
- Peninsula High (Continuation)High · 123 students
Other schools in Millbrae
- Taylor MiddleMiddle · 756 students
- Spring Valley ElementaryElementary · 375 students
- Meadows ElementaryElementary · 360 students
- Green Hills ElementaryElementary · 338 students
Nearby schools
- Spring Valley Elementary0.2 mi · 375
- Franklin Elementary0.4 mi · 357
- Burlingame Intermediate0.5 mi · 1,115
- Taylor Middle0.6 mi · 756
- Lincoln Elementary0.8 mi · 415
- Green Hills Elementary1.1 mi · 338
Frequently asked questions
About Mills HighHow large is Mills High?
Mills High enrolls approximately 1,115 students in grades 09-12.
What grades does Mills High serve?
Mills High serves grades 09-12.
How many teachers does Mills High have?
Mills High employs 54 FTE teachers, for a student-to-teacher ratio of 20.5:1.
What is the racial breakdown of students at Mills High?
At Mills High, the student body is approximately 11% White, 20% Hispanic, 0% Black, 59% Asian, 9% Two or more.
Is Mills High public or private?
Mills High is a public K-12 school, overseen by San Mateo Union High.
Data sourceSchool profile facts are sourced from the NCES. Community content is posted by allk12 members.