The Common Core Sanity Check of the Day: Estimation Is Not a Fuzzy Math Skill

Oops, he did it again. Eric Owens, the infamous Daily Caller “reporter” who has never seen a silly math problem he wasn’t willing to ascribe to the Common Core (the truth be damned!), has published yet another howler deploring a math problem purportedly of Common Core lineage. But this time he trades his trademark dishonesty for mathematical ignorance.

This flawed “front-end estimation” method wasn’t invented by the people behind Common Core. The concept—which refers to the correct answer to an addition problem as merely “reasonable” and allows students to be off by over 22 percent in their estimation—has been around for decades.

At the same time, the methodology is aligned with the Common Core State Standards Initiative, which attempts to standardize various K–12 curricula around the country.

This math lesson is just one more in the constantly burgeoning inventory of hideous Common Core math problems.

Being mathematically ignorant myself, I asked Jason Zimba, a lead author of the Common Core standards, if the standards do in fact promote this approach. Here’s what he had to say:

State standards have always set expectations for estimating the results of computations. Here for example was one of the previous California standards from grade 3:

“Use estimation to verify the reasonableness of calculated results.”

And here was one of the previous Indiana standards from grade 2:

“Use estimation to decide whether answers are reasonable in addition problems.”

And here was one of the previous Massachusetts standards from grade 4. This one specifically mentions front-end estimation:

“Select and use a variety of strategies (e.g., front-end, rounding, and regrouping) to estimate quantities, measures, and the results of whole-number computations up to three-digit whole numbers and amounts of money to $1000, and to judge the reasonableness of the answer.”

I chose examples from these particular states because critics of the Common Core sometimes point to these particular states’ previous standards documents as models. (Indeed, these states’ standards were important inputs to the Common Core development process, along with other sources of evidence.)

The examples weren’t hard to find in any case. Prior to the Common Core, a 2005 study of the math standards of forty-two states found that forty-one of these states had expectations for estimating results of computations. Some of these state standards documents mentioned specific estimation techniques, while others did not.

Unlike the previous Massachusetts standards, the Common Core doesn’t mention front-end estimation. Over the years, math educators have discussed the issue of which are the best estimation techniques to teach students. Different textbooks approach this differently. But there’s no question that estimation is important. It’s an antidote to the blind use of calculators, and it’s obviously an important life skill.

I noticed that the worksheet also requires the exact sum. Estimation should not displace exact computation. The Common Core standards never mention estimation in the content standards that set an expectation of fluency with the standard algorithms; by design, those standards are pristine and maximally direct.

So to summarize: the state math standards celebrated by Common Core opponents, such as those previously in place in California, Massachusetts, and Indiana, all expected students to learn how to estimate. The Common Core standards are clear that estimation is no replacement for computation. And in fact, the Common Core standards save estimation until after students have mastered their math facts. So what’s the controversy again?

The Daily Caller thinks estimation is “impossibly stupid” and will “make your kid a moron.” Based on a perusal of recent Daily Caller articles, perhaps that’s just a wee bit of projection.

-Mike Petrilli

This first appeared on the Fordham Institute’s Flypaper blog.

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