The student-teacher ratio is the number of students enrolled divided by the number of full-time-equivalent (FTE) teachers. Across US public schools in 2024-25, there were 15.3 students per teacher on average.
It is not class size
The ratio counts every teacher on staff, including special education teachers, reading specialists, art and music teachers, and teachers who work part time (counted as fractions). Typical classroom sizes are almost always larger than the ratio.
Why ratios vary
- Small rural schools often have low ratios because they need a minimum number of teachers.
- Schools with large special education programs tend to have lower ratios.
- Virtual schools can report very high ratios.
- State staffing rules and budgets differ widely.
How we show it
We show a ratio only when both enrollment and teacher counts are reported. On school and district pages we compare it with the district, state and US figures. In rankings we include only districts with at least 1,000 students. A lower ratio is not proof of better teaching; it is one staffing measure.
Sources
Written by the BCER.org editorial team.