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Concrete + Abstract = Math Learning
Andrew Watson
Andrew Watson

Early math instruction includes daunting complexities.

We need our students to understand several sophisticated concepts. And, we need them to learn a symbolic language with which to represent those concepts.

Take, for example, the concept of equivalence. As adults, you and I can readily solve this problem :   3+4 = 4 + __

Early math learners, however, can easily stumble. Often, they take the equals sign to mean “add up all the numbers,” and believe the correct answer to that question is “10.”

How can we help them through this stage of understanding?

Strategy #1: Switch from Abstract to Concrete

The first answer to the question seems quite straightforward. If the abstract, symbolic language of math (“3+4=___”) confuses students, let’s switch to a more concrete language.

For instance: “If my frog puppet has three oranges, and your monkey puppet has four oranges, how many oranges do they have together?”

It just seems logical: the switch from abstract to concrete ought to help.

Alas, those concrete examples have a hidden downside.

As Dan Willingham argues in Why Don’t Students Like School?, humans naturally focus on surface features of learning.

When children see monkeys and frogs and oranges, they associate the lesson with those specific entities–not with the underlying mathematical properties we want them to learn.

In edu-lingo, concrete examples can inhibit transfer. Students struggle to transfer a lesson about oranges and puppets to anything else.

Strategy #2: “Fade” from Concrete to Abstract

Taking their cue from Jerome Bruner, psychology researchers wondered if they could start with concrete examples and then, over time, switch to more abstract examples.

For instance, students might start learning about mathematical equivalence by using a balance. When they put an equal number of tokens on both sides, the balance is level.

In the second step, they do practice problems with pictures of a balance and tokens.

And, in the final step, they see abstract representations: 2 + 5 = 5 + __.

They describe this technique as “concreteness fading.”

And, sure enough, it worked. In this case, “worked” meant that students who learned equivalence though a concreteness fading method transferred their knowledge to different–and more difficult–problems.

They did so better than students who learned in a purely abstract way. And, better than students who learned in a purely concrete way. (And even, as a control condition, better than students who started with an abstract representation, and then switched to concrete.)

By the way: these researchers tested their hypothesis both with students who had a relatively low level of knowledge in this area, and those who had a high level of knowledge. They got (basically) the same results both times.

An Essential Detail

When we teachers try to incorporate psychology research into our teaching, we can sometimes find that it conflicts with actual experience.

In this case, we might find that our young math learners just “get it” faster when we use frog puppets. Given that experience, we might hesitate to fade over to abstract teaching.

This research shows an intriguing pattern.

Sure enough, students who began with concrete examples made fewer mistakes on early practice problems. And, that finding was true for both the “concrete only” group and the “concreteness fading” groups.

In other words, the “abstract only” group did worse on the early practice problems than did those groups.

But…and this is a CRUCIAL “but”…the “concrete only” group didn’t do very well on the transfer test. Their raw scores were the lowest of the bunch.

However, the “concreteness fading” group did well on the early problems AND on the transfer test.

It seems that, as the researchers feared, too much concrete instruction reduced transfer.

 

In sum: “concreteness fading” gives young math learners both a helpfully clear introduction to math concepts and the abstract understanding that allows transfer.


Fyfe, E. R., McNeil, N. M., & Borjas, S. (2015). Benefits of “concreteness fading” for children’s mathematics understanding. Learning and Instruction35, 104-120.

When Good Classroom Assignments Go Bad
Andrew Watson
Andrew Watson

As an English teacher, I rather love this assignment for 9th graders reading Romeo and Juliet:

Choose a character from the play.

Write a short monologue–20 lines or so–exploring that character’s feelings about a particular moment, or another character.

Be sure to write in iambic pentameter.

This assignment lets my students explore a character’s point of view in thoughtful detail. It encourages empathy and imagination. And, it allows them to play with a poetic meter that’s been at the rhythmic heart of English literature since we had English literature.

So, again, as an English teacher I love it.

But as someone who knows from cognitive science, I fear it’s simply not going to work (for most 9th graders on the planet).

Good Intentions Meet Cognitive Limitations

Regular readers know that students use their working memory all the time to grok their classroom work.

Working memory is vital to all classroom learning. And, alas, we just don’t have very much of it.

And, this assignment (almost certainly) places far too great a demand on my students’ WM.

Students must use their WM to…

…choose among the characters of the play. (Yes: choices take up WM resources.)

…choose among the dramatic events their chosen character experiences.

…create a wisely empathetic response to a dramatic event. (Yes: creativity requires working memory.)

And, on top of that, to…

…express richly Shakespearean logic and emotion within a tightly structured, largely unpracticed poetic meter. (If you doubt that writing in iambic pentameter takes working memory, try rewriting this sentence in iambic pentameter. Your prefrontal cortex will be aching in no time.)

So much cognitive load will overwhelm all but the most inventive of students.

Solving the Problem

Given that this assignment could be so powerful, how might we adapt it to fit within working memory limitations?

Two strategies come quickly to mind.

Firstredistribute the working memory demands. That is: don’t have them do all the WM work at the same time.

In this case, that suggestion can be easily implemented.

First night’s homework: choose the character, and describe or outline the dramatic moment.

Second night’s homework: write the monologue in modern English.

This approach spreads out the working memory demands over time. All the choosing, and some of the creativity, happens on the first night. The rest of creativity happens on night #2.

Secondreduce the working memory demands. Unless your students have practiced with iambic pentameter A LOT more than my students have, they’re likely to struggle to compose 20 fresh lines.

My own teacherly instincts would be to have them experiment with existing poetry. For instance, a fun sonnet might serve as a scaffold for early, tentative work.

In sonnet 130, Shakespeare famously laments the use of extravagant metaphors to hyper-praise women:

My mistress’ eyes are nothing like the sun.

Coral is far more red than her lips’ red.

And yet, by heav’n, I think my love as rare

As any she belied with false compare.

Can my students devise their own version of these sentiments? And, can the preserve the meter?

My boyfriend’s eyes are not as blue as sky.

For reals, his abs just aren’t what you’d call “shredded.”

And yet, by heav’n, I think my guy as hott

As any bae that Beyoncé has got.

Of course, scaffolding is called “scaffolding” because we can take it down. So, once students can manage iambic pentameter with this level of support, we can prompt them to devise more and more free-form iambic creations.

With enough practice, they might–some day–be able to compose 20 fresh lines of their own.

Can Multiple-Choice Tests Really Help Students?
Andrew Watson
Andrew Watson

Multiple-choice tests have a bad reputation. They’re easy to grade, but otherwise seem…well…hard to defend.

After all, the answer is RIGHT THERE. How could the student possibly get it wrong?

Given that undeniable objection, could multiple-choice tests possibly be good for learning?

The Benefits of Distraction

A multiple-choice test includes one correct answer, and other incorrect answers called “distractors.” Perhaps the effectiveness of a multiple-choice question depends on the plausibility of the distractors.

So, a multiple choice question might go like this:

“Who was George Washington’s Vice President?”

a) John Adams

b) Mickey Mouse

c) Tom Brady

d) Harriet Tubman

In this case, none of the distractors could possibly be true. However, I could ask the same question a different way:

“Who was George Washington’s Vice President?”

a) John Adams

b) Thomas Jefferson

c) Alexander Hamilton

d) James Madison

In THIS case, each of the distractors could reasonably have held that role. In fact, all three worked closely with–and deeply admired–Washington. Two of the three did serve as vice presidents. (And the other was killed by a VP.)

Why would the plausibility of the distractor matter?

We know from the study of retrieval practice that pulling information out of my brain benefits memory more than repeatedly putting information into it.

So, we might hypothesize this way:

If the distractors are implausible, a student doesn’t have to think much to figure out the correct answer. No retrieval required.

But, if the distractors are plausible, then the student has to think about each one to get the answer right. That’s lots of retrieval right there.

In other words: plausible distractors encourage retrieval practice, and thereby might enhance learning.

Better and Better

This line of reasoning leads to an even more delicious possibility.

To answer that question about Washington’s VP, the student had to think about four people: Adams, Jefferson, Hamilton, Madison.

Presumably she’ll learn the information about Adams–who was the correct answer to the question.

Will she also learn more about the other three choices? That is: will she be likelier to answer a question about Alexander Hamilton correctly? (“Who created the first US National Bank as Washington’s Secretary of the Treasury?”)

If the answer to that question is YES, then one multiple-choice question can help students consolidate learning about several different facts or concepts.

And, according to recent research, the answer is indeed YES.

The research paradigm used to explore this question requires lots of complex details, and goes beyond the scope of a blog post. If you’re interested, check out the link above.

Classroom Implications

If this research holds up, we might well have found a surprisingly powerful tool to help students acquire lots of factual knowledge.

A well-designed multiple-choice question–that is: one whose plausible distractors require lots of careful thought–helps students learn four distinct facts or concepts.

In other words:

“Multiple-choice questions…

a) are easy to grade

b) help students learn the correct answer

c) help students learn information about the incorrect answers

or

d) all of the above.”

Me: I’m thinking d) sounds increasingly likely…