How NCES Collects School Data: The Common Core of Data
The Common Core of Data (CCD) is the US Department of Education’s annual census of public schools and districts. This page explains how it is collected and how this site uses it.
The National Center for Education Statistics (NCES), part of the Institute of Education Sciences, runs the CCD as a census — not a sample survey. Every state education agency reports administrative records for every public elementary and secondary school and local education agency (LEA) in its jurisdiction, following common definitions in the CCD survey instruments. Because it is a census of state records, CCD totals are the official counts used across the federal government, and discrepancies usually trace to how a state classifies an agency or a program, not to sampling error.
The file families this site uses
Directory files identify every school and agency: names, NCES identifiers, addresses, grade spans, operational status and school counts. Membership files carry fall enrollment by grade, race and sex; the “Education Unit Total” rows this site uses are the published totals for each school, district and state. Staff files report full-time-equivalent staff by role, including classroom teachers. Lunch files report counts of students eligible for free and reduced-price meals under the National School Lunch Program. Completers files count credentials awarded, including regular secondary school diplomas. Finance files — the F-33 district survey and the NPEFS state survey — are collected with the US Census Bureau and report revenues and expenditures under a standard accounting handbook.
Editing, imputation and flags
NCES edits state submissions for consistency and flags every value: reported, imputed, adjusted or missing. Where a state cannot report an item, NCES may impute it from the agency’s prior-year data or from similar agencies, and the flag travels with the value in the file. This site republishes values as published, including imputed ones, because the flags are part of the official record; but where a district’s item is simply missing, our pages say “not reported” and show no number at all rather than substituting our own estimate. Response and imputation detail for each file is documented in the NCES release notes for the 2023–24 v.1a files, which are the exact versions used here.
Identifiers make joins possible
Every school carries a 12-character NCESSCH identifier and every agency a 7-character LEAID. Those keys are what let this site join a district’s enrollment to its teachers, its schools’ lunch counts and its F-33 finance record without name-matching errors. They also expose genuine quirks of the system — New York City’s 32 geographic districts, statewide districts in Hawaii and Puerto Rico, and supervisory unions in New England — which our pages describe rather than smooth over.
Related reading: why data years are staggered, how we compute student–teacher ratios, and the methodology index.
Data: National Center for Education Statistics (NCES) Common Core of Data and EDFacts, retrieved October 2026, from nces.ed.gov. Enrollment, staffing and lunch figures are for the 2023–24 school year; finance figures are fiscal year 2024 (school year 2023–24) unless a page labels them otherwise.
Disclaimer: Public School Stats republishes official federal statistics for general information only. Figures are reported as published by NCES and EDFacts and may include imputed or revised values; for decisions affecting a specific school or district, confirm the figure with the district or the NCES source file. See our full Disclaimer.