The Post Fails Math

One of the ways you know a particular story has really embedded itself in the public consciousness is when it becomes a genre. As in the "People who think public education should teach X blame NCLB for reduced attention, resources, etc. for X" story, of which roughly 632,000 have been published in major media outlets in the last five years. Today's version in the Post focuses on music education, and contains a significant error. It says:

Despite research showing that students who study music have better attendance, achievement and lifetime earnings, music classes are struggling to survive. Supporters of such classes place some of the blame on the federal No Child Left Behind law....As instructional time in math, language arts and other subjects students must achieve proficiency in has risen, time devoted to other subjects has declined. Time spent on arts and music in 2007 is about half what it was before No Child Left Behind became law in 2002, according to a report recently released by the nonprofit Center on Education Policy.

The sentence I've italicized above is not even close to being right.

You can read the Center on Education Policy report referred to in the article here. It only shows detailed data for changes in instructional time for elementary schools. According to the report, the districts surveyed devoted 110 minutes per week to art and music in 2007. Districts that reduced time for art music reported an average reduction of 57 minutes. 110 minutes is not "about half" of 167 minutes, it's 65.8%, a hair below two-thirds.

Much more importantly, only 16 percent of districts reported reducing time for art and music at all.

Needless to say, this is a hugely important distinction. The plain meaning of the sentence printed in the Post is that NCLB has caused a 50% reduction in the total time spent teaching art and music. The report suggests that the actual number is closer to five percent (.34 X .16). In other words, the story is wrong by as much as an order of magnitude.

This seems like a classic symptom of the objectivity / accuracy value imbalance in the media -- newspapers will go to great lengths to make sure that a political reporter's spouse's friend's cousin's college roomate didn't buy lemonade from a stand in front of the candidate's neighbor's house, yet they make math mistakes like this all the time.