Sunday, April 9, 2017


One way to understand the effort a district puts into class size is to compare general fund per-pupil expenditures compared with average student teacher ratios. Districts in the state have different per-pupil expenditure amounts, depending on the amount of local support they receive in addition to state funding. These amounts do not include expenditures from school plant or bond funds, which are typically used for maintenance and repairs or for construction of buildings.

District Efforts with Student-Teacher Ratios

We conducted this analysis using data from the State Department of Education from the 2014-15 school year. We used district financial summaries to calculate the number of elementary and secondary full-time equivalent (FTE) positions by districts with over 100 FTE, and compared with general fund per pupil expenditures (GFPPE).

The analysis did not produce average class size figures. The elementary and secondary FTE include a number of positions that did not provide direct instruction in the regular classroom - elementary reading specialists and elementary music teachers, for example. In fact, the analysis produced student-teacher ratios instead, but in general provided a stable comparison showing effort on the part of the district to control ratios.

We decided to omit data from the analysis  for two districts whose funding levels are much higher than the norm in Idaho - Blaine County and McCall-Donnelly. Idaho's average per-pupil general fund expenditures in 2014-15 were $6302. Blaine County's GFPPE were $17,174 and McCall's were $12,426. Average student-teacher ratio (STR) in the two districts were 12.7 and 13.6, respectively - very low, as you might expect.

For the remainder of the districts, we ran a scattergram comparing the two factors which allowed us to assess the average student-teacher ratio efforts of these districts considering their PPE. The results are interesting.

It's important to understand that the chart shows STR and expenditures compared to the Idaho average; we made no attempt herein to compare to other states.

PPE and student-teacher ratios are negatively correlated (about -.7), as you might expect. In general. higher PPE districts have lower student-teacher ratios.

  • Sandpoint (LPO), Boise, Lewiston, and Moscow all have low STR and high PPE. 
  • Weiser and Caldwell, with low PPE compared with the state average, have surprisingly low STR, below the state average.
  • Vallivue and Preston have the highest STR among the districts in the comparison.
  • West Ada, and Nampa's average STR are higher than Kuna and Post Falls, which have comparable general fund expenditures.
So that's a broad brush picture of how districts use funding to deal with student teacher ratios. It's important because class size is viewed as an important factor in student success in most studies. Here's an entire website devoted to the research on class size.

Next - the third part of this series - how districts pay teachers considering the funding they have.