I will protect your pensions. Nothing about your pension is going to change when I am governor. - Chris Christie, "An Open Letter to the Teachers of NJ" October, 2009

Tuesday, January 14, 2014

Christie's Useless School Time Proposal in Three Graphs

So Chris Christie implemented "Operation Ignore Bridgegate" today at his State of the State address with a proposal that was sure to make reformies swoon:
Despite the improvements we are seeing in Newark and Camden, I believe we need to take bigger and broader steps to adjust our approach to K-12 education to address the new competitive world we live in. Our school calendar is antiquated both educationally and culturally. Life in 2014 demands something more for our students. It is time to lengthen both the school day and school year in New Jersey.
If student achievement is lagging at the exact moment when we need improvement more than ever in order to compete in the world economy, we should take these steps – every possible step – to boost student achievement.
And one key step is to lengthen the school day and the school year. So, working with Commissioner Cerf, I will present to you shortly a proposal to increase the length of both the school day and the school year in New Jersey. This is a key step to improve student outcomes and boost our competitiveness. We should do it now. [emphasis mine]
Nothing, of course, about how to pay for it, or what it would look like, or how it would affect collective bargaining, or whether it would be a huge unfunded mandate... Golly, if I were cynical, I would have thought this was just slapped together to distract us from something!

But let's put all that aside and ask a simple question: will it work? Is there a correlation between the length of the school day and student achievement? Luckily, we can go to the NJDOE and look at the data files - because schools are required to report both the length of their school day and the amount of instructional time their students receive. Let's see if there's a connection by starting with this:

So what we have here is a scatterplot that shows the relationship between two variables: how many 8th graders in a school are "above proficient" on the state's annual math test, and the percentage of students in the school who qualify for the federal free lunch program - the best proxy measure we have for economic disadvantage. Each dot is a school: where it lies on the graph depends on the two variables.

See what happens? In general, as a school's free lunch eligible (FL) percentage goes down, the percentage of 8th graders who pass the state test goes up. Obviously, poverty affects student learning: the dynamics are very clearly understood. 

In geek terms, that "R-squared" number in the bottom corner tells us that about 57% of the variation in the proficiency rate is "explained" by the FL rate. You can see how that red line, called a "regression line," gives us a pretty good prediction of what a school's proficiency rate would be if we knew what its FL percentage was.

Now, for comparison, let's see if there is a similar relationship between the length of particular school's day and its proficiency rate on the 8th grade math test:

In the previous graph, there was a fairly strong relationship between FL and test scores; but here, we see that there is no practical relationship between those same test scores and the length of the school day. See how much smaller the R-squared number is? It's telling us that even if we knew the length of a school's day, it would be nearly impossible to predict how that school did on the 8th Grade math test.

And what about instructional time - the amount of time students are actually learning?

In New Jersey, there is no correlation between the time a school's students are in class and how many students pass the state test.

If Chris Christie really wanted to increase test scores, he wouldn't propose lengthening the school day; he would propose a way to lift every child's family out of poverty.

So why would he bring up this useless idea today? Thinking...

h/t the always excellent Rob Tornoe

Note: I only included schools that had more than a five hour school day so as not to corrupt the results with some outliers. There are a few schools in New Jersey, apparently, that have very short school days; they may serve special populations, or only have part-day Pre-K and K programs. Just keepin' it real, folks.


mrslewischem said...

Where have we heard this before? In Chicago, candidate Rahm Emanuel screamed loudly and as often as his cronies could pay protesters to hold upside down signs, that Chicago had the shortest school day in the world. He told community leaders that the spigot of funds would be turned off if they did not support his longer school day and he told the public that teachers got raises and kids got the shaft"

This works because the school day and year have never aligned themselves with the work day and year. When I asked why he was so laser-focused on the longer school day, he told me "I can't have kids on the street on 1:30". I responded - "Oh -so this is a babysitting, warehousing scheme". And that's when I got cussed out.

The school reformers playbook gets passed around like a mash note since Broad infected "leadership" and TFA-stained staffers, the politicians are always looking for something for nothing. They don't even have to come up with new talking points.

It would be lovely if they could be truly innovative and original. But that would require real critical thinking skills. And of course, their children go to private schools where they have world languages, PE, the arts (all of them), science, social studies 3 libraries and they're not in school all day or all year. They have unionized teachers who are trusted and valued.

Let's face it. They're preparing our children for the world of drudgery work, while their children learn to rule. And that's the status quo on steroids.

Karen Lewis

Marie Corfield said...

I love how your graphs come from the DOE itself. Wonder if, when push comes to shove, they will have the courage to defend their own research?

JanetM said...

Doesn't anyone from the media find it odd, hypocritical, CRAZY dissonant that Christie himself pays Delbarton upwards of $30,000 a year to keep his son in school for 6 hours a day, 163 days a year? This model is good enough for the children of the elites, but not for our kids?

Giuseppe said...

Wow, Karen Lewis and Marie Corfield read JJ! Way to go.

Randy said...

This proposal is nothing but another way to gut collective bargaining. This number of days that a teacher works and the length of the school day are negotiated items.

Mrs. King's music students said...

Ooh, ooh! I may know how we're paying for extended day. I visited a charter school today and was told to come early because Fridays are always half-days. So yeah - an hour longer M through Thurs, offset by the half-day on Fridays. See? I never would have known this if I hadn't gone there myself.

Mike Klonsky said...

To quote the late, great educator John Goodlad:

However, a need to expand the length and breadth of schooling does not necessarily follow from well-founded arguments regarding the critical importance of education. As I have said repeatedly, schooling and education are not synonymous.