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Thursday, October 25, 2012

Wrong Questions About Spreadsheet Math

Spreadsheets are a ubiquitous and necessary tool these days. Students need to learn spreadsheet math.

"Our children still spend hundreds of hours perfecting their ability to add, subtract, multiply, and divide fractions. And the pinnacle of math for most of our K-12 students remains the ability to solve quadratic equations. When was the last time you used any of these skills? When did you last multiply two three-digit numbers together on paper, add two improper fractions with unlike denominators, or solve a quadratic equation?"

These are the questions people asked when it came to calculator use, and they are still the wrong questions. Spreadsheet math will not replace the ability to actually understand math any more than calculators did.

When the National Council of Teachers of Mathematics (NCTM) recommended calculators for even the youngest students, they rhapsodized about about how calculators would revolutionize math teaching, using the same sort of language that idealizes the potential of spreadsheet math.

"By teaching our children spreadsheet math we enable them to solve ...fascinating problems, problems without a single right answer, problems that can be explored, problems that get our children thinking "out of the box."

And that was exactly the wrong-headed pie-in-the-sky rationale for recommending calculators. It sounds great but does not work in practice. The problem with math instruction is not whether we should be using calculators or spreadsheets. The problem is the lack of skilled math teachers. The problem is the continued reliance on teaching tricks and shortcuts instead of math. Like calculators, spreadsheets have a similar tendency to replace thinking.

Beginning in 2001, I researched the calculator fallacy extensively culminating in a 78-page report in 2010. Briefly, I found that the research NCTM insisted supported the use of calculator in the early grades did not exist.

I agree that students need to learn spreadsheets, but not as a substitute for learning math. Since our elementary teachers lack an ability to teach math for understanding, abundant experience with mechanical processes, though far from ideal, is pretty much the only way kids learn to tell an unreasonable answer from a reasonable one, and even then they are not very good at it.

Just last week, a friend's eighth grade daughter (A+ in math per last progress report) was sure that if $27.50 could buy 10 lbs of hamburger, then $55.00 would buy over 150 lbs because "I followed all the steps correctly." When I told her that obviously she had not, she argued that even the calculator agreed with her, so I must be the wrong one. Just yesterday she insisted that -3 + ½ = -3½ (by analogy to 2 + ½ = 2½). In her mind, all you have to do is get rid of the plus sign and shove the fraction up against the whole number. When these kinds of misconceptions plague even good students, no wonder students who are not as “good” have math anxiety. Deep down, the anxiety is related to an unspoken and unspeakable suspicion that math makes no sense. They are right. When math is turned into a system of tricks and shortcuts, it makes no sense.