First, at least one school district is encouraging parents to give their kids bananas to improve their MAP test scores:

Other schools base their test motivators on scientific research. At Hanna Woods Elementary in the Parkway district, for example, students taking the test will get goody bags from younger students that include No. 2 pencils and mints. Peppermint, according to research from the University of Cincinnati, can help increase concentration.

At Kennerly Elementary in the Lindbergh School District, the parent association encouraged parents to donate bananas, which are rich in mind-boosting potassium.

Does anybody seriously believe that students’ scores are low because they have a potassium deficiency? Bananas won’t have any effect on test scores, but they do provide a distraction from the things that do determine achievement, like quality of curriculum and teaching. It’s not entirely the districts’ fault, though. There are so many constraints on the hiring, firing, and rewarding of teachers that it’s easier to turn to bananas, despite the minuscule marginal returns.

And now for the second banana story: “fair-trade” bananas are available at Wash U. The bananas come with certification that the farmers who grew them were compensated appropriately. This is basically an extension of the locavore idea. All the bananas in a market are going to be priced about the same, because if one brand were much more expensive, it wouldn’t sell. So in order to pay farmers a lot more, you have to cut back on some other cost of bringing the bananas to market — like transportation costs. So, you buy more from farmers who are close by, and less from farmers who are farther away (and who are so in need of money that they offer bananas very cheaply). Transportation is just one example; there are other costs you can cut back on. You can work only with farmers you already know, and avoid spending money on finding new people to exchange with. The point is, there will always be some farmers out there who are farther away or harder to find, who will be hurt by “fair trade.”