The student/teacher ratio for regular public elementary schools declined from 1990 through 2006, while the student/teacher ratio for regular public secondary schools was of similar size in 1990 and 2006.

The ratio of students to teachers, which is sometimes used as a proxy measure for class size, declined between 1990 and 2006, from 17.6 to 15.9 students per teacher for all regular public schools (see table A-31-1). The student/teacher ratio for regular public elementary schools also declined from 1990 through 2006 (from 18.2 to 15.6), with most of the decline occurring after 1996. In contrast, the student/teacher ratio for all regular public secondary schools increased between 1990 and 1996 (from 16.7 to 17.6) and then declined to 16.6 in 2006. In regular public combined schools (schools that include both elementary and secondary grades), the student/teacher ratio fluctuated between 14.4 and 16.1 between 1990 and 2006 but was of similar size in 2006 and 1990 (15.7 vs. 15.8) (not all data shown). While in 1990 the student/teacher ratio for elementary schools was higher than that of secondary schools and combined schools, in 2006, the student/teacher ratio for elementary schools was lower than that of secondary schools and of similar size to that of combined schools.

In every year from 1990 through 2006, the student/teacher ratio was positively associated with the enrollment size for elementary, secondary, and combined regular public schools: the student/teacher ratio for any given enrollment category was always higher than that of any smaller enrollment category. For example, in 2006, regular secondary schools with 1,500 students or more enrolled 6.5 more students per teacher, on average, than regular secondary schools with enrollments under 300 students.

Generally, the student/teacher ratio of public elementary schools in each enrollment category declined from 1990 through 2006, except in the largest schools (1,500 students or more) where the student/teacher ratio fluctuated over this period with a low of 19.4 in 2006 and a high of 21.2 in 1996 (not all data shown). Student/teacher ratios for regular public secondary schools in each enrollment category increased from 1990 through 1996 and then declined from 1996 through 2006. For regular public combined schools, student/teacher ratios for the smallest and largest enrollment categories were higher in 2006 than in 1990, and the student/teacher ratios for the middle three enrollment categories were lower in 2006 than in 1990.

The student/teacher ratios for public alternative, special needs, and vocational schools fluctuated from 1990 through 2006. For alternative schools and vocational schools, the student/teacher ratios were higher in 2006 than in 1990, while for special education schools the student/teacher ratio was lower in 2006 than in 1990.

In 2006, the student/teacher ratio for public schools with higher percentages of students approved for free or reduced-price lunch was generally smaller than the ratio of schools with lower percentages approved for this benefit (see table A-31-2). Also, the student/teacher ratios of schools in cities (16.3) and suburban areas (16.2) were generally larger than those of schools in towns (15.3) and rural areas (14.8). Within rural areas, the student/teacher ratio was largest in the fringe areas (15.8) and smallest in remote areas (12.6).

Technical Notes

Student/teacher ratios do not provide a direct measure of class size. The ratio is determined by dividing the total number of full-time-equivalent teachers into the total student enrollment. These teachers include classroom teachers; prekindergarten teachers in some elementary schools; art, music, and physical education teachers; and teachers who do not teach regular classes every period of the day. Teachers are reported in full-time-equivalent (FTE) units. This is the amount of time required to perform an assignment stated as a proportion of a full-time position. It is computed by dividing the amount of time an individual is employed by the time normally required for a full-time position. This analysis excludes schools that did not report both enrollment and teacher data. Regular schools include all schools except special education schools, vocational schools, and alternative schools. Charter schools can be of any school type. For more information on the Common Core of Data (CCD), see supplemental note 3. For more information on free and reduced-price and locale codes, see supplemental note 1.