ROCKFORD, Ill. – Students do better academically when their regular teachers are in the classroom on a consistent basis.

One study, from the National Bureau of Economic Research (NBER), came to the conclusion that when a teachers is absent for at least 10 days per year, it has a significant impact on student learning.

That message has apparently been lost in two Illinois school districts – Rockford and Harlem.

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Students in both districts struggle academically.

On the 2012-13 Illinois Standards Achievement Test (ISAT), only 40.9 percent of Rockford students met or exceeded standards, compared to 59.8 percent statewide. On the Prairie State Achievement Examination (PSAE), 38.6 percent of Rockford students made the grade, compared to 53.3 percent statewide.

Harlem students did better, but were still not up to par. On the ISAT, 52.5 percent met or exceeded standards, compared to 59.8 percent statewide. On the PSAE, 49.2 percent of Harlem kids made the grade, compared to 53.3 percent statewide.

Is teacher absenteeism as least a small part of the problem?

The Rockford teachers union contract gives eligible employees a total 12 paid sick days per year, and allows two of them to be used for personal days.

In 2013-14, approximately 2,000 Rockford employees (the majority of them teachers) took a combined 23,165 sick and personal days off, which averages out to 11.5 days per year.

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That exceeds the 10 day per year threshold noted in the NBER study.

The Harlem union contract gives eligible employees 15 paid sick days per year, of which three can be used for personal days.

In 2013-14, 467 Harlem teachers took a total of 6,022 sick and personal days, which averages out to 12.9 days per teacher.

A lot of learning time was obviously lost in both school districts.

That type of absenteeism also cost both districts a lot of money. That’s never good news, particularly for districts that recently experienced significant financial problems.

In 2012 the Harlem school board voted to lay off 22 teachers and 39 support staff employees to save the district approximately $4 million, according to news reports.

In 2011 the Rockford school board announced $52 million worth of budget cuts, including the layoff of more than 300 employees and the closing of seven schools, according to news reports.

In 2013-14, Rockford employees were paid a combined $7 million for sick and personal days they took. The district did not disclose how much it had to spend on substitute teachers that year.

Harlem teachers were paid a combined $2 million dollars for sick and personal days in 2013-14. The district was also forced to spend $408,660 on wages for substitute teachers.