The average public elementary school class in the United States had 19.1 students in the 2020-21 school year, according to the National Center for Education Statistics (NCES). That figure covers teachers in self-contained classes, meaning one teacher with the same group of students for all or most of the day in several subjects.
Classes got bigger in the upper grades. Teachers in departmentalized instruction, who teach several different groups of students in one or more subjects, averaged 22.0 students per class in middle schools and 21.0 in high schools, NCES reported.
The numbers come from the National Teacher and Principal Survey (NTPS), which asks a national sample of teachers about their own classes. NCES sampled about 68,300 teachers in about 9,900 public schools for the 2020-21 round. As of October 2026, the NTPS table library lists no state class-size table from a newer round.
Class size by state
California had the largest elementary classes, at 23.0 students, followed by Utah at 22.0 and Michigan at 21.5. Maine had the smallest at 14.2, then Vermont at 14.9 and the District of Columbia at 15.8. That puts 8.8 students between the top and bottom states (23.0 minus 14.2).
In high schools, Nevada (27.6) and California (27.1) had the biggest departmentalized classes. Maine was again the smallest at 13.4, with Alaska and Vermont tied at 15.4. California also led middle schools at 27.5, and Maine was lowest at 14.2.
Nine states averaged 20 or more students in elementary classes. Eleven, counting the District of Columbia, averaged fewer than 17.
| State | Elementary (self-contained) | Middle school (departmentalized) | High school (departmentalized) |
|---|---|---|---|
| United States | 19.1 | 22.0 | 21.0 |
| Alabama | 17.5 | 23.6 | 20.1 |
| Alaska | 16.6 | 18.7 | 15.4 |
| Arizona | 20.4 | 25.4 | 22.6 |
| Arkansas | 18.8 | 20.8 | 17.2 |
| California | 23.0 | 27.5 | 27.1 |
| Colorado | 18.8 | 23.7 | 22.4 |
| Connecticut | 18.0 | 19.5 | 18.6 |
| Delaware | 17.9 | 26.1 | 21.6 |
| District of Columbia | 15.8 | 16.3 | 19.1 |
| Florida | 17.9 | 22.8 | 23.4 |
| Georgia | 20.3 | 23.3 | 22.4 |
| Hawaii | 17.5 | 18.8 | 20.1 |
| Idaho | 21.2 | 23.1 | 20.5 |
| Illinois | 18.7 | 21.0 | 21.1 |
| Indiana | 21.3 | 22.6 | 19.6 |
| Iowa | 19.8 | 21.1 | 19.5 |
| Kansas | 17.9 | 19.8 | 17.4 |
| Kentucky | 19.8 | 23.5 | 20.0 |
| Louisiana | 18.3 | 20.9 | 20.9 |
| Maine | 14.2 | 14.2 | 13.4 |
| Maryland | 18.3 | 23.4 | 22.0 |
| Massachusetts | 16.7 | 20.1 | 17.4 |
| Michigan | 21.5 | 24.7 | 23.4 |
| Minnesota | 20.9 | 25.9 | 23.6 |
| Mississippi | 18.9 | 20.5 | 17.9 |
| Missouri | 18.2 | 18.5 | 19.2 |
| Montana | 18.1 | 18.8 | 16.2 |
| Nebraska | 18.9 | 20.8 | 16.8 |
| Nevada | 18.5 | 26.0 | 27.6 |
| New Hampshire | 16.0 | 16.6 | 16.8 |
| New Jersey | 16.9 | 20.0 | 19.1 |
| New Mexico | 17.6 | 19.8 | 20.1 |
| New York | 16.9 | 19.5 | 19.6 |
| North Carolina | 18.5 | 22.1 | 20.4 |
| North Dakota | 16.8 | 19.0 | 15.8 |
| Ohio | 19.2 | 20.7 | 18.6 |
| Oklahoma | 19.7 | 19.3 | 16.7 |
| Oregon | 21.0 | 23.0 | 22.6 |
| Pennsylvania | 18.4 | 20.7 | 19.4 |
| Rhode Island | 19.5 | 19.2 | 20.5 |
| South Carolina | 17.9 | 21.3 | 20.1 |
| South Dakota | 19.0 | 21.3 | 19.7 |
| Tennessee | 18.6 | 20.6 | 19.9 |
| Texas | 17.7 | 21.6 | 20.1 |
| Utah | 22.0 | 24.8 | 22.1 |
| Vermont | 14.9 | 14.6 | 15.4 |
| Virginia | 17.8 | 20.9 | 20.9 |
| Washington | 19.0 | 23.1 | 22.2 |
| West Virginia | 16.4 | 18.4 | 17.7 |
| Wisconsin | 18.2 | 22.8 | 22.2 |
| Wyoming | 16.1 | 18.3 | 16.1 |
Source: NCES, National Teacher and Principal Survey, Public School Teacher Data File, 2020-21 (table: Average class size in public K-12 schools, by school level, class type, and state). Figures are weighted survey estimates. NCES counts a school as elementary if it offers at least one of grades K through 4 and has more elementary than middle grades; middle schools offer at least one of grades 5 through 8; high schools enroll students in more of grades 9 through 12 than in lower grades. None of the figures shown carry an NCES caution flag.
Why class size and student-teacher ratio differ
Class size counts the students in a teacher's room. Student-teacher ratio divides total enrollment by the total number of teachers, counted as full-time equivalents (FTE), so two half-time teachers count as one. That second number includes teachers who don't lead a regular class. In a note on its state ratio table, NCES says the ratio "includes teachers for students with disabilities and other special education teachers; these teachers are generally excluded from class size calculations."
The NTPS notes also list other teaching arrangements outside the two class types above, including elementary subject specialist classes, team-taught classes, and pull-out or push-in classes, where a specialist works with students outside or inside their regular room. In elementary schools, 14% of public school teachers taught classes like these in 2020-21, according to the table notes.
So a state's ratio tends to run below its average class size. Nationally, public schools had 15.2 students per FTE teacher in 2024-25, according to allk12's analysis of NCES Common Core of Data. That is 3.9 fewer than the 19.1-student average elementary class (19.1 minus 15.2), though the two figures come from different years and different federal data collections.
| State | Average elementary class, 2020-21 | Students per FTE teacher, 2024-25 | Difference |
|---|---|---|---|
| United States | 19.1 | 15.2 | 3.9 |
| California | 23.0 | 21.6 | 1.4 |
| Utah | 22.0 | 21.6 | 0.4 |
| Texas | 17.7 | 14.9 | 2.8 |
| New York | 16.9 | 11.3 | 5.6 |
| Vermont | 14.9 | 11.3 | 3.6 |
| Maine | 14.2 | 11.3 | 2.9 |
Class size: NCES National Teacher and Principal Survey, 2020-21. Ratio: allk12's analysis of NCES Common Core of Data, 2024-25, total students divided by total FTE teachers at operating public schools that reported both. The national ratio leaves out Tennessee, whose 2024-25 school teacher counts are missing from the data.
New York shows the widest gap of these states. Its ratio of 11.3 students per teacher is among the lowest in the country, while its average elementary class held 16.9 students, or 5.6 more. In Utah the two numbers nearly match: 22.0 students per class and 21.6 per teacher. allk12's student-teacher ratios by state rank all 50 states and DC on the ratio side.
Some states set class-size limits in law. In Texas, Section 25.112 of the Education Code says a school district "may not enroll more than 22 students in a prekindergarten, kindergarten, first, second, third, or fourth grade class." The law lifts the limit for 12 weeks of each school year, and the state education commissioner can exempt a district for a school year if the limit "works an undue hardship on the district." Texas's average elementary class, 17.7 students in 2020-21, was 4.3 below that cap.
Florida has class-size limits in its state constitution. Article IX, Section 1, amended by citizen initiative in 2002, caps the number of students assigned to each teacher at 18 in prekindergarten through grade 3, 22 in grades 4 through 8, and 25 in grades 9 through 12. It also says the class size requirements "do not apply to extracurricular classes."
Sources
NCES: Average class size in public K-12 schools, by school level, class type, and state, 2020-21
NCES: 2020-21 NTPS Methods and Procedures
NCES Digest of Education Statistics: Table 208.40, pupil/teacher ratios by state
Texas Legislature: Education Code Chapter 25, Section 25.112
Florida Senate: Constitution of the State of Florida, Article IX, Section 1
Student-teacher ratios from allk12's analysis of National Center for Education Statistics (NCES) Common Core of Data, 2024-25.
