Because I need something to blow off steam about, and because some random commenter (which you can find under this video) was yammering about overpaid teachers, I decided to put together a facts package on Wisconsin teachers.
According to http://teacherportal.com, Wisconsin teachers have the second-lowest initial teacher salary of any state (behind North Dakota only) at $25,222/year on average (the 2011 federal poverty rate for a one-person household is $10,890). They make an average salary of $46,390/year, 20th highest in the country (California tops the list with an average pay of $59,825), and has increased by 21.5% over the last decade (eighth-least in the U.S). Mississippi tops the list with an increase of 46.8% over the last decade. It should be noted that the site doesn't specify where it gets its data, or whether those stats include both college and K-12 teachers (although a specifically K-12 list on payscale.com shows that the number for each state listed is significantly lower than the number in the teacherportal link). Finally, the site doesn't specify when its data was collected.
Using that data, a blogger on freeby50.com correlated it with median income by state and found that under that figure, Wisconsin teachers get 89% of the state median income ($52,224). Can't say I'm that convinced by this guy; he mixes up the terms 'mean' and 'median', but he also appears to be the only person who's done this kind of analysis.
The best data probably comes from the U.S. Census, which concluded that primary and secondary schoolteachers in Wisconsin made $49,100/year in 2008. Primary schoolteachers made $49,200 and secondary school-teachers made $48,800. This is slightly less than the national average, which was $52,800 (both), $52,400 (primary) and $53,300 (secondary) in 2008. Twenty-one states had higher averages than Wisconsin; California again led with $65,800/year.
According to a different Census .pdf, the average went up to $52,900 in 2009.