Arroyo Seco Junior High
Valencia, CA · Middle School · Grades 7-8
Arroyo Seco Junior High is a middle school in Valencia, CA with 1,217 students enrolled and a 70% proficiency rate. Part of William S. Hart Union High. NCES data from the U.S. Department of Education.
Get Arroyo Seco Junior High's new scores when they post
We'll email you the moment Arroyo Seco Junior High changes. No spam — only real updates.
About This School
Arroyo Seco Junior High is a middle school located in Valencia, California. The school serves 1,217 students in grades 7-8. The student-to-teacher ratio is 24.8:1.
According to EDFacts assessment data, 70% of students meet grade-level proficiency standards in combined math and reading.
17% of students qualify for free or reduced-price lunch.
Arroyo Seco Junior High is part of the William S. Hart Union High in California.
How This School Compares
Arroyo Seco Junior High has 1,217 students enrolled, making it smaller than the average school in William S. Hart Union High (1,311 students). Its 70% proficiency rate is 11 percentage points above the district average of 60%. Compared to the California state average of 45%, the school performs 25 points higher. The 24.8:1 student-teacher ratio is above the national average of 16:1.
Frequently Asked Questions
Arroyo Seco Junior High has 1,217 students enrolled in grades 7-8. The student-to-teacher ratio is 24.8:1.
According to EDFacts data, 70% of students at Arroyo Seco Junior High meet grade-level proficiency standards in combined math and reading assessments.
Arroyo Seco Junior High is part of the William S. Hart Union High in Valencia, California. You can view all schools in this district on the district page.
All data on this page comes from the National Center for Education Statistics (NCES) Common Core of Data and EDFacts assessment results. These are official federal datasets published by the U.S. Department of Education.
School profiles are built from NCES directory data and EDFacts assessment results. Proficiency rates reflect combined math and reading performance. Graduation rates are reported for high schools with available data.
The this entity record above pulls directly from NCES Common Core of Data and EDFacts. What follows is the per-entity context — how this entity sits in the broader U.S. K-12 school outcomes and enrollment distribution and which underlying factors drive the headline numbers.
The methodology behind every numeric value on this page is publicly documented on the NCES Common Core of Data and EDFacts portal and described in detail on this site’s methodology page. Refresh cadence varies by underlying series; the page surfaces the as-of date for each number so readers can trace any figure back to the source release.
Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for this entity’s peers within U.S. public schools and districts. A single-entity reading without peer context can be misleading when an entity is an outlier on one axis but typical on another.
Source: NCES Common Core of Data, 2026.