## Training the Congressional Budget Office of tomorrow

Why we hate Common Core instruction, Part 4,307:

Well, okay, fine — but if you already have the answer, why would you need a simultaneous estimate of the answer? Do we have such little faith in ourselves? And when I fill out my tax return, can I round \$291 in income down to \$200?

Once again, Tom Lehrer proves prescient: “In the new approach, as you know, the important thing is to understand what you’re doing rather than to get the right answer.”

1. ### fillyjonk »

30 September 2013 · 1:12 pm

That gives me flashbacks to the circa 1977 version of New Math that made doing long division twice as long. And my being kept in at recess until I could demonstrate I could do that method, even though I could get the correct answer by the reasonable “old fashioned” method my mother had taught me the summer before.

And, is adding two numbers really so hard you need to estimate to make sure you’ve done it right? Why not just add them a second time to check yourself? And I say this as someone who gives her students “hints” on how to make sure their answers are reasonable, like “If you are calculating a geometric mean and the number you get is 10 times larger than any of the numbers in the dataset, you certainly did something wrong.”

2. ### jsallison »

30 September 2013 · 5:32 pm

3. ### McGehee »

30 September 2013 · 8:50 pm

I can add those two numbers in my head without worrying about digits; 291 being (300 – 9), the sum would be 354 + 300 – 9, or 654 – 9, or 645.

“Front-end estimation”? That’s for economists, who not only don’t need the right answer, getting it is a disqualification for most jobs in the field.

4. ### fillyjonk »

1 October 2013 · 10:59 am

I could totally rant on about the “feel good about your answer” trend. I’ll just observe that one reason I LIKED math in school is that there were clear cut right and wrong answers.

5. ### Roger Green »

3 October 2013 · 5:29 am

This may be a mere academic (wrong word) question for some of you but I have a 4th grader, and I don’t know how to help her. http://blog.timesunion.com/rogergreen/please-help-me-with-my-daughters-math-homework/3690/