## Friday, January 2, 2015

### Favorite comments of '14, cont: Ze'ev Wurman, Barry Garelick, Auntie Ann, eddie sacrobosco, and concerned

Ze'ev Wurman said...
"This experience would serve me well, I thought. If I ever got to interview for a teaching job and I was asked to describe how I would work within the Common Core standards, I could say “Getting the right answer isn’t enough; students have to show their reasoning” or some such language."

Nice! :-)

But why to insist on equations? Aren't pictures, "visual fractions," and "area models" good enough? We need no stinkin' equations in Common Core! Another :-)

Barry Garelick said...
Thanks for the smiley, Ze'ev. And not to torpedo my own work, but it occurs to me that the interviewer could say "And what do you think of 'guess and check' as a reasoning strategy?" Oops. Guess I better seek employment in a car wash!

Auntie Ann said...
Answer: I believe it is important for students to work real-world problems, and the real world doesn't come with an answer key to check against. An engineer often has no way to check their calculations. If an aircraft engineer is wrong, the plane crashes. People in the real world who use math have to have a reliable method for attaining the answer.

They also will be fired if they spend all day guessing and checking instead of reaching a quick and reliable answer.

Guess-and-check is simply not a real-world method.

Anonymous said...
Guess and check is only an acceptable way to reach an answer if the possible options are VERY limited. Adults use it all the time (in our heads) when there are only 2 or 3 possible answers. So you can introduce it to children on that basis, using a few examples that show that this is an OK method ONLY if it gets you to the answer very quickly.

eddie sacrobosco said...
@Auntie Ann

When I used to teach word problems in Beginning Algebra I would tell students, "You may be able to solve these word problems without equations, but I'm not so much interested in the answers as I am in the writing of the equations. If I were only interested in answers the questions would be A LOT harder. And if you're interested in just answers, go take an engineering class because they're mostly interested in answers - but your answers better be right!"

And the equations are a great way to convince someone else that your answers are right!

concerned said...
You might provide students with an example that's prepared in advance, for addressing this question, with solution (5+5/7, 2-2/7). One in which guessing the solution is highly unlikely.