Key words aren’t the key to understanding math

Students in NYC recently finished taking the state math test. As a result, I’ve spent the past couple of weeks watching a lot of test prep going on in classrooms. One of the strategies I see being used over and over is the use of key words.

I admit that I was guilty of using this strategy when I started teaching. I was puzzled when my students could flawlessly perform computations but struggled with word problems. Teaching them to look for key words seemed like an easy fix to this. I had charts in my room listing all the key words and their corresponding operations. Yet, the key words didn’t seem to help them.

So why don’t key words work?

It’s because they don’t allow students to use what they already know to make sense of a situation.

The research backs this up. Drake and Barlow (2007) gave a student the problem below.

There are 3 boxes of chicken nuggets on the table. Each box contains 6 chicken nuggets. How many chicken nuggets are there in all?

Guess what a student who looked for key words answered? 9 chicken nuggets. The student saw the words: “in all” as a signal to add 6 and 3. I would bet that the student could have made sense of this situation and arrived at the correct answer if he drew a picture or reasoned about it. However, using key words led him to an incorrect answer.

Key words encourage students to take a short cut instead of making sense of a situation. If students think about what makes sense, they don’t need shortcuts or key words. They don’t need to worry about what happens when they aren’t any key words or when there are multiple key words in a story.

If we believe that doing mathematics should have meaning for students and make sense to them, then teaching key words doesn’t support those goals. Teaching students to reason about a situation and know why they are performing an operation does.

Have you used key words with your students? What was your experience?

Drake, J. M., & Barlow, A. T. (2007). Assessing Students’ Levels of Understanding Multiplication through Problem Writing. Teaching Children Mathematics, 14(5), 272-277.

6 thoughts on “Key words aren’t the key to understanding math

  1. Pingback: One Strategy for Attacking Word Problems | Bridging The Gap

  2. New Math Coach

    I used key words teaching 7th grade math for years. As a matter of fact it was included in the textbook in a table “You can translate many words for operations into symbols.” No reasoning required!
    At the moment I am coaching elementary math and am working hard to have children understand the problem before they start to find a solution. And for teachers to teach that way.
    The other day I modeled this with a simple word addition problem that I did not put the numbers in (4th grade). I asked kids what they would have to do to solve it and most knew they had to add. When I asked “How do you know that?” most of them chose words in the problem that they thought indicated addition – there were none. No one said because that makes sense! This was an eye opener to the teachers watching.

    Reply
    1. Nicora Placa Post author

      Wow! That is a powerful example. It’s so hard to shift student thinking so that math is about sense-making instead of following the directions the teacher or textbook gave. I’d love to hear more what else you are doing to help them reason mathematically.

      Reply
  3. Sue Meredith

    I agree. I used the key word method long ago, when I started teaching and it was in vogue, but found out quickly that it didn’t work. Students would pick out the numbers, look for a key word and perform an operation to solve, but they had no understanding of the problem. I began by requiring them to at least label the answer. That required a bit more thinking. Then I began teaching them to analyze the problem by reading all of it and then re-reading each part and representing it with a picture or symbols. Now I teach older students problem types by category and developed a graphic organizer for each one, requiring them to label each part. They can now solve problems with much more independence and explain much more about what the problem is telling and what it is asking. I teach special education student with severe language delays, so if this works for them, it’s a pretty robust intervention.

    Reply
    1. Nicora Placa Post author

      It’s great to hear that you found an intervention that works. I’d love to know more about the types of categories you use since I think that being able to make connections between different problems is so important.

      Reply
  4. Sue Meredith

    I forgot to mention that I also started writing problems where I spelled out the numbers instead of including numerals. That was a shock for some of them at first, and reduced the scan and check method a bit.

    Reply

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