Changing Up Popular Warm-Up Routines
Originally posted October 16, 2020
As with any task — warm-up or curricular — I try to think of ways to boost student engagement, tap into different ways of thinking, and just keep things fresh.
WODB (Which One Doesn’t Belong?) has become a classroom staple, and for good reason. (Although, does it even qualify as an acronym if no one pronounces it as a word? We're all still saying the full phrase, right?) Here's the first one I came across on the site — I added the numbers 1 to 4:
I do my homework first, in the order that the shapes come to mind:
#2 doesn’t belong because it’s the only non-triangle.
#4 doesn’t belong because it’s the only shaded shape.
#1 doesn’t belong because it’s the only one with exactly one line of symmetry.
#3 doesn’t belong because it’s the only obtuse triangle.
Then with students, I flip the routine:
I give them a blank grid and ask them to draw sketches as they listen to my clues. I don’t show the original image — instead, I give each clue one at a time and let them build the visual. They may need to revise as they go.
The reveal is so fun. Then they compare sketches and critique each other’s drawings.
Estimation 180 is another go-to. Here’s Day 6:
Instead of asking, “How many almonds are there?” I ask:
One of the four numbers below is correct.
Which one is it and why?
Which number is way off?
8
15
28
40
This framing tightens up the reasoning. It also helps students who get anxious about guessing. For younger students, I might give three options instead of four.
Open Middle problems are fantastic, but they’re easily tweakable too. Here’s one labeled Grade 4: Equivalent Fractions.
Use digits 1–9, at most once, to make three equivalent fractions.
I put red/yellow counters labeled 1 through 9 into a baggie. I pull out a digit — say, 5 — and ask:
"Which space (A–G) can the number 5 not go in?"
This question is way more approachable than, “Where should 5 go?” With the first, students are evaluating. With the second, they’re guessing. The safe, focused question gets better thinking — and builds on classmates’ reasoning. Some might decide that 5 doesn’t fit anywhere and toss it in the discard pile. (Also helps avoid the classic mistake of using a number twice.)
And I’ll be honest — when I saw this problem in a recent online workshop, I didn’t even try it. Because these are my truths:
Someone else will solve it before I do.
The answer will be revealed before I get far.
So... what’s the point of trying?
How many of our students feel the same way?
[Added 10/17/2020]
I meant to include a numerical WODB example — the kind that sparks lots of ideas. Here's the first one from the site, labeled A–D:
My thinking:
D is the only non-square number.
A is the only single-digit number.
C is the only number divisible by 5.
B is the only even number.
I give students these clues in order. They’re not allowed to erase — only cross off — so I can see what they thought originally.
These tweaks don’t require reinvention — just a shift in how the routine is delivered. And when students get used to the structure, they can help co-create, which is the best kind of learning.