Data Dictionary

Welcome to the Delaware School Data Dictionary!

This guide explains all the metrics, data fields, and terminology used throughout the Delaware School District Finder and related applications. All data is sourced from the Delaware Department of Education and updated annually.

Table of Contents

Enrollment & Demographics

Total Enrollment

A snapshot of enrollment in Delaware is collected every year on the last business day before September 30th. The student count includes any student who was enrolled and in attendance in a school for the last ten school days of September.

The September student count is the main base of funding for schools in Delaware (Title 14 of the Delaware Code) and includes various levels of funding based on educational needs. This count does not include students who may have enrolled after September 30th. Enrollment covers preschool through 12th grade in traditional school districts, charter schools, and vocational-technical schools.

Race/Ethnicity Distribution

The percentage of students in each racial and ethnic category:

  • White – Students who identify as White
  • Black or African American – Students who identify as Black or African American
  • Hispanic or Latino – Students who identify as Hispanic or Latino (any race)
  • Asian – Students who identify as Asian
  • Multi-Racial – Students who identify with two or more races
  • American Indian/Alaska Native – Students who identify as American Indian or Alaska Native
  • Native Hawaiian/Pacific Islander – Students who identify as Native Hawaiian or Pacific Islander

Student Characteristics

Special population percentages reported with enrollment (Delaware Report Card “Other Characteristics” and “Residence” groups):

  • Low Income (also labeled Economically Disadvantaged) — Beginning in school year 2013–2014, low income is determined by students who receive TANF or SNAP (Direct Certification) benefits, not free or reduced-price lunch eligibility.
  • Students with Disabilities – Students receiving special education services under IDEA
  • English Learners – Students learning English as an additional language
  • Homeless – Students experiencing homelessness as defined by the McKinney-Vento Act (reported under Residence)

Average Class Size

Average Class Size Distribution

Average class size shares the average amount of students in each class. Class size is measured differently in elementary schools compared to middle and high schools.

Average class size for kindergarten through 3rd grade is reviewed by the district/charter office for accuracy. A district/charter board may submit a class size waiver if the class size average is above 22 students per Delaware Code (§ 1705A). For all grades above 3rd grade, average class size is calculated using the average class size in primary subject areas, such as English Language Arts and math.

On school detail pages, this appears as a distribution of classes across size buckets (for example, 0–10 students, 11–15 students, and so on), showing how many classes fall in each range and what share of classes that represents.

School year notation: School year is represented by the last year of the school year. For example, the 2018–2019 school year is shown as 2019.

Academic Performance

English Language Arts Proficiency

The percentage of students who were proficient in English language arts (ELA) during the current school year.

Students in grades 3-8 are annually assessed in ELA using the Smarter assessment, and in 11th grade by the SAT assessment. More than 95% of students take the SAT, regardless of college or career path after graduation.

Mathematics Proficiency

The percentage of students who were proficient in mathematics during the current school year.

Students in grades 3-8 are annually assessed in mathematics using the Smarter assessment, and in 11th grade by the SAT assessment. More than 95% of students take the SAT, regardless of college or career path after graduation.

Note: Proficiency percentages represent students meeting or exceeding grade-level standards. Assessment types vary by grade level (Smarter for grades 3-8, SAT for grade 11).

Graduation Rates

Note that graduation rates are only available for high schools.

4-Year Graduation Rate

The percentage of students who graduated high school in 4 years with a regular high school diploma.

This represents the most recent graduating class (typically Class of 2024). It shows what percentage of students who started 9th grade together completed their diploma in the standard 4-year timeframe.

5-Year Graduation Rate

The percentage of students who graduated high school in 5 years with a regular high school diploma.

This shows the graduation rate for students who took an additional year beyond the standard 4 years to complete their diploma (typically Class of 2023). This metric recognizes that some students need extra time to meet graduation requirements.

6-Year Graduation Rate

The percentage of students who graduated high school in 6 years with a regular high school diploma.

This shows the graduation rate for students who took two additional years beyond the standard 4 years to complete their diploma (typically Class of 2022). This extended timeframe provides opportunities for students facing significant challenges.

Important: The 4-year, 5-year, and 6-year graduation rates are for different cohorts of students, not the same students tracked over time. Each represents a different graduating class, allowing comparison of how different cohorts performed.

College & Career Readiness

Note that college and career readiness metrics are only available for high schools (and combined-grade schools that include high school).

College and/or Career Ready

The percentage of students who finished 12th grade college and/or career ready in the most recent school year.

How It’s Measured: College and Career Readiness is measured by the percentage of students who successfully complete academic or technical coursework and demonstrate mastery of that skill area by the end of 12th grade.

Qualifying Indicators: Students can demonstrate readiness through any of the following:

  • Advanced Placement (AP) – Passing AP exams
  • International Baccalaureate (IB) – Completing IB programs
  • SAT Essay – Proficiency on SAT essay portion
  • Dual Enrollment – Successfully completing college courses while in high school
  • ASVAB – Armed Services Vocational Aptitude Battery qualifying scores
  • Multi-Literacy – Demonstrating proficiency in multiple literacies
  • Industry Recognized Credentials – Earning professional certifications
  • Work-Based Learning – Completing structured work-based learning programs

Why This Matters: This metric recognizes that students can be successful through multiple pathways – not just traditional college prep. It values both academic achievement and technical/vocational preparation equally.

Graduate College Enrollment

College enrollment captures the number of Delaware graduates who enrolled in public and private colleges both in- and out-of-state by the fall semester after graduation.

Detail pages show the count and percent of graduates who enrolled (often labeled “Graduates enrolling in college”), plus a breakdown by college type:

  • Delaware Public College
  • Non-Delaware Public College
  • Delaware Private College
  • Non-Delaware Private College
  • Total

This is a cohort measure and may reflect an earlier graduating class than the most recent school year shown for other metrics.

AP Courses & Exams

Available for high schools and combined-grade schools that offer Advanced Placement. Separate from the College and/or Career Ready snapshot metric, which bundles AP with other readiness pathways.

AP Courses Offered & Exam Outcomes

Advanced Placement (AP) courses are college-level courses that many colleges will recognize for credit if the student passes the end of course exam. The AP Courses Offered measure shares the total unique courses offered. Each school decides whether to offer AP courses and which courses to offer.

School and district detail pages present yearly AP figures, including courses offered, student course enrollments, assessments taken, assessments passed, and the percent of assessments passed.

The Advanced Placement program is administered by The College Board. Several AP assessments are available; evaluation of each is related to specific coursework. This metric area excludes both AP Seminar and AP Capstone. A passing assessment grade for AP is currently a 3 or higher.

The Report Card also publishes International Baccalaureate (IB) course and assessment data in the same metric family. A passing assessment grade for IB is currently a 4 or higher. Our detail pages currently focus on the Advanced Placement rows from that dataset.

Feeder Boundaries

What Are Feeder Boundaries?

Feeder boundaries are the geographic attendance zones that determine which students attend which schools. These boundaries can vary by grade level.

Key Points:

  • Grade-Specific: Some schools have different boundaries for different grades (e.g., K-5 elementary might have one boundary, 6-8 middle another)
  • Not All Schools Have Boundaries: Only 177 out of 289 schools have geographic feeder boundaries. Charter schools, special programs, and some vocational-technical schools use open enrollment instead
  • Boundary Schools: Traditional public schools that serve students based on where they live
  • Choice Schools: Charter schools and some magnet programs that don’t have geographic boundaries – students can apply from anywhere in the state

NCES Grades vs. Boundary Grades

There are two different ways grades are represented in the data:

  • NCES Grades: The official grade levels that a school serves (e.g., “K-5”, “6-8”, “9-12”)
  • Boundary Grades: The grade levels for which geographic boundary data is available

These may not always match! A school might serve K-8 but only have boundary data for K-5 (meaning the middle school grades might use a different enrollment process). Use boundary grades when looking at feeder patterns.

School Types & Levels

Education Levels

Schools are categorized by the grade levels they serve:

  • Kindergarten (K): Schools serving only kindergarten
  • Elementary (E): Schools primarily serving grades K-5 or 1-5
  • Elementary/Middle (EM): Schools serving a combined elementary and middle school range (e.g., K-8, 1-8)
  • Middle (M): Schools primarily serving grades 6-8
  • High School (H): Schools primarily serving grades 9-12
  • Adult Education (AE): Programs for adult learners
  • Other (O): Specialized programs, alternative schools, or programs serving multiple non-standard grade configurations

School Types

Schools are classified by governance structure:

  • Traditional Districts and Schools: A public school operating by a local school district. Students are assigned a particular school based on their home address, with the option to apply to another public school through Delaware’s School Choice and lottery process.
  • Charter Schools: A public school operating independently under an approved charter. Charter schools accept students from across Delaware through the School Choice and lottery process.
  • Vocational Schools: A public school operating by a local school district. Vocational schools accept students within their Delaware county through the School Choice and lottery process.
  • Special Programs: A public school serving specific student populations (e.g., Intensive Learning Centers, Alternative Programs)

Data Sources & Updates

Primary Data Sources

  • Delaware Open Data Portal: GeoJSON files for school locations and feeder boundaries
  • Delaware DOE ESSA API: Performance metrics, enrollment, demographics, contact information
  • Delaware Report Card: Official state reporting system (reportcard.doe.k12.de.us)

Update Frequency

Annually: Data is updated once per year, typically in late summer before the new school year begins.

  • Geographic Boundaries: Updated when school attendance zones change
  • Performance Metrics: Reflect the most recently completed school year
  • Enrollment: As of September 30 enrollment count (official count date)
  • Demographics: Based on enrollment data collected at the start of the school year

School Year Notation

The current data reflects the 2024-2025 school year, meaning:

  • Current enrollment: As of September 30, 2024
  • Performance metrics: Results from 2024-2025 testing
  • 4-Year Graduation Rate: Class of 2024 (graduated June 2024)
  • 5-Year Graduation Rate: Class of 2023 (graduated June 2023, started 9th grade in 2018)
  • 6-Year Graduation Rate: Class of 2022 (graduated June 2022, started 9th grade in 2016)
  • Average class size: School year shown as the ending calendar year (e.g., 2024 ≈ 2023–24)
  • Graduate college enrollment: Cohort-based; may lag other metrics (e.g., fall-after-graduation enrollment for an earlier class)
  • AP courses & exams: Reported by school year for each year in the table

Understanding Missing Data

Why Some Data Shows “N/A” or “-“

You may see “N/A” (Not Available) or “-” (dash) for certain metrics. These indicators appear for different reasons:

  • Grade Level Mismatch: Elementary schools won’t have graduation rates; high schools won’t have early childhood metrics (shown as “N/A”)
  • Data Suppression: Data may be suppressed to protect student privacy, typically when fewer than 10 students in a category (shown as “-“)
  • Insufficient Sample Size: Sample size not significant enough for reliable reporting (shown as “-“)
  • Not Yet Available: Data not available for the current reporting period (shown as “-“)
  • Special Programs: Alternative schools, Intensive Learning Centers (ILCs), and special programs may not participate in standard assessments (shown as “N/A”)
  • New Schools: Recently opened schools may not have historical data yet (shown as “N/A”)
  • API Limitations: Some specialized schools don’t have complete data in the state reporting system (shown as “N/A”)

Dash (-) Values: A dash indicates that data was not available. This could mean the data has been suppressed to protect student privacy (typically when fewer than 10 students), it’s not available for the current reporting period, or the sample size is not significant enough to report. The table uses dashes (displayed as “-” in our tables) to indicate any of these situations where data cannot be displayed.

Understanding Performance Ratings

Color-Coded Performance Indicators

Performance metrics are color-coded to provide quick visual reference:

Excellent (≥80%): Dark green – Significantly above average

Good (60-79%): Light green – Above average

Average (40-59%): Orange – Meeting basic expectations

Needs Improvement (<40%): Red – Below expected performance

Note: These color bands are for quick visual reference only. Always review the full Delaware Report Card for comprehensive school performance analysis and context.

Additional Information

For More Information

Additional resources for understanding Delaware school data:

Questions or Corrections?
Metric definitions are based on Delaware Department of Education Report Card Element descriptions (ESSA API) and official documentation. For the most authoritative information, please consult the Delaware Report Card directly.