Back in November, Jason Richwine and Andrew Biggs released a report for the Heritage Foundation that strove to construct a fair comparison of public-school teacher compensation with the remuneration received by comparable workers in the private sector.  A subsequent op-ed by Biggs provides a good overview:

Public school teachers are important and should be paid fairly. Despite conventional wisdom, their salaries are fair and their fringe benefits far outclass private sector jobs. And the overpayment of teachers isn’t chicken-feed – it’s a large portion of total education spending at a time when states and localities are strapped for cash. Once we acknowledge that underpaid teachers aren’t the reason our education system performs poorly, we can start working on reforms that might actually put things right.

All told, “more generous fringe benefits for public-school teachers, including greater job security, make [their] total compensation 52 percent greater than fair market levels, equivalent to more than $120 billion overcharged to taxpayers each year.”

That conclusion is the splash headline, of course, but the full report is worth a read, not the least because it incidentally raises the bias that can be built into the numbers that we all bat around in the public debate.  The most striking, in this particular case, comes from the core reason that Bureau of Labor Statistics (BLS) data shows public school teachers to be underpaid.  The following comes from a footnote in the relevant BLS report:

In these cases, the daily work schedule would be the length of the school day plus any time teachers are required to be in school before or after the school day, and the weekly work schedule would be the daily schedule multiplied by 5 days (Monday through Friday). The number of weeks would be 37 (185 days ÷ 5 days per week). The time not worked during summer, Christmas break, and spring break would be excluded from the work schedule and would not be considered vacation or holiday. Jobs in schools are not considered to be seasonal.

“Jobs in schools are not considered to be seasonal,” yet time off is not “considered vacation or holiday.”  So, those weeks that most private sector employees are working are, for public school teachers, neither workdays nor paid days off nor unpaid days off.