"On any given day in the USA, about one in 20 teachers is absent from school," USA Today reports. "Between kindergarten and 12th grade, the typical kid spends the equivalent of two-thirds of a school year being taught by a substitute teacher."
The newspaper cites a new study by Raegan Miller, a former teacher union president, who found that teacher absenteeism costs about $4 billion annually for substitute-teacher salaries and administrative costs. The author also found that Mondays and Fridays are by far the most popular days to call in "sick."
On a related note, KOCO-TV reports that a substitute teacher at Edmond Memorial High School (where I recently snapped this photo) was arrested on -- you guessed it -- Friday. The poor gal was drunk in class.
UPDATE: Here's Dave with the "Top Ten Signs Your Teacher Is Drunk."