In the LCMS, we've always had a strong doctrine of what it means to be called. It was a term reserved for our clergy, our male clergy (we only have male clergy).
Ministers have certain protections under the tax system. They balance out the additional penalties that Ministers get because they are regarded as self-employed by the Social Security System, and therefore must pay the full 15%, and are regarded as employees by the IRS, and therefore get no tax breaks as self-employed.
Way back, the Synod decided to invoke the title "commissioned minister" upon our male teachers. Since they don't get paid well, and they have families to support, lets extend those benefits to them. Then, of course as female teachers became more prominent and didn't necessarily stop teaching just because they got married, and because it was sexist and the title was meaningless anyway -- it was extended to female teachers as well.
All of this goes against the good sense of reserving the title of Minister for the clergy. It confuses our doctrine. Since this has happened, the Office of the Ministry has lost some of the respect that it once had.
Now, because of the nebulousness of the "commissioned minister" title, an LCMS school teacher has opened the flood gates and given the Obama Administration exactly what they always wanted, the possibility of applying discrimination and employment laws to the Church. She signed a contract when she received a call as a "commissioned minister" but now argues that she really wasn't so that she can win a discrimination suit. I don't envy her health issues, and am not sure why the church school contracted another teacher instead of bringing in a long term substitute -- maybe one wasn't available, but they shouldn't have contracted a teacher to fill her position for the entire year. But the Obama Administration is using this as an opportunity to argue that the nondiscrimination laws are so unbiased that they need to be applied to church situations as well. Here's another story as well.
And...the school is closed down. They've partnered with another church, but these children are not hearing God's Word, and the battle is before the public eye. I'm sure Satan is happy.