This article makes a fundamental error, and its sad they never even acknowledge it.<p>You can&#x27;t talk about the value of a good teacher without mentioning supply or demand. Yes, I know, here we go again. But this is basic economics. If the United States decided to train 100,000,000 good teachers, you can bet that the 100,000,000th teacher will not add the same value to the country as the first. There likely won&#x27;t even be anyone for the 100,000,000 teacher to teach! Yet this is what the author here assumes. That the value add of a good teacher is constant. No mention of supply or demand whatsoever.<p>Fortunately, there&#x27;s a clever trick we use to incorporate supply and demand into value-determination. It&#x27;s called the market.<p>Unfortunately for students, teachers unions have done their best to destroy a free market for teachers, school are usually not even <i>allowed</i> to pay better (in the schools eyes) teacher more as per union contracts. And this country has no doubt suffered for it. All for a few extra thousand in the average teacher&#x27;s pockets, its sickening.