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David K Butler

@davidkbutler.bsky.social

Maths Learning Support lecturer at Adelaide Uni (my views here). Grad Dip Ed & PhD Finite Geom. Love maths and helping people learn. he/him

1,853 Followers  |  682 Following  |  6,613 Posts  |  Joined: 10.10.2023
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Posts by David K Butler (@davidkbutler.bsky.social)

Here goes…

12 * 18
= 24 * 9
= 24*10 - 24
= 240 -20 -4
= 220 - 4
= 216

Wait.

12* 18
= 6*2*3*6
= 6*6*6
=216 because I happen to know what 6^3 is.

10.03.2026 10:56 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Looking through some family papers today with my brother and came across a description of my great-grandmother, Lottie, who gave birth to at least fourteen children between 1913 and 1933. Lottie’s occupation was listed as HOME MANAGER which seems both remarkably apt and feminist for the time.

10.03.2026 09:56 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

Change approved!

10.03.2026 10:00 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

*sigh* Trying to figure out my own solutions to work things will always get me into trouble won't it?

10.03.2026 02:55 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
A long curving purple-grey stalk grows without leaves directly out of the ground. On the end are at least ten trumpet-shaped flowers made of six curling pink petals. Each has several long stamens sticking out of its mouth.

A long curving purple-grey stalk grows without leaves directly out of the ground. On the end are at least ten trumpet-shaped flowers made of six curling pink petals. Each has several long stamens sticking out of its mouth.

#bloomscrolling

10.03.2026 01:47 β€” πŸ‘ 3    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
In the background are many tough green leaves with a prominent central vein and smaller veins coming off at right angles. Where these leaves meet are four frangipani flowers. Each flower has five oval-shaped petals circled slightly in the centre where they overlap. The petals are white at the edge and yellow in the centre.

In the background are many tough green leaves with a prominent central vein and smaller veins coming off at right angles. Where these leaves meet are four frangipani flowers. Each flower has five oval-shaped petals circled slightly in the centre where they overlap. The petals are white at the edge and yellow in the centre.

#bloomscrolling

10.03.2026 01:53 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
In the background are many tough green leaves with a prominent central vein and smaller veins coming off at right angles. Where these leaves meet are four frangipani flowers. Each flower has five oval-shaped petals circled slightly in the centre where they overlap. The petals are white at the edge and yellow in the centre.

In the background are many tough green leaves with a prominent central vein and smaller veins coming off at right angles. Where these leaves meet are four frangipani flowers. Each flower has five oval-shaped petals circled slightly in the centre where they overlap. The petals are white at the edge and yellow in the centre.

#bloomscrolling

10.03.2026 01:53 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
A long curving purple-grey stalk grows without leaves directly out of the ground. On the end are at least ten trumpet-shaped flowers made of six curling pink petals. Each has several long stamens sticking out of its mouth.

A long curving purple-grey stalk grows without leaves directly out of the ground. On the end are at least ten trumpet-shaped flowers made of six curling pink petals. Each has several long stamens sticking out of its mouth.

#bloomscrolling

10.03.2026 01:47 β€” πŸ‘ 3    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
A bright yellow daisy with separated petals and a very fluffy centre. Other daisies in various stages and green leaves are in the background.

A bright yellow daisy with separated petals and a very fluffy centre. Other daisies in various stages and green leaves are in the background.

#bloomscrolling

10.03.2026 01:39 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 2    πŸ“Œ 0
A bright yellow daisy with separated petals and a very fluffy centre. Other daisies in various stages and green leaves are in the background.

A bright yellow daisy with separated petals and a very fluffy centre. Other daisies in various stages and green leaves are in the background.

#bloomscrolling

10.03.2026 01:39 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 2    πŸ“Œ 0

It's things like this that make me think I am not in spirit an academic. There are a lot of things about academic life I just don't understand or want.

09.03.2026 23:46 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

For no reason in particular, I am remembering one of my previous bosses saying that the money from our national teaching award should be used on "nice things for yourself, like going to a conference" and wondering how she didn't see that conferences were just a LOT of work and inconvenience.

09.03.2026 23:45 β€” πŸ‘ 5    πŸ” 0    πŸ’¬ 0    πŸ“Œ 1
Museum sign showing a roaring sabretooth cat. A small child is included for size comparison, and looks like he's about to boop it.

Museum sign showing a roaring sabretooth cat. A small child is included for size comparison, and looks like he's about to boop it.

DO NOT BOOP THE KITTY

05.03.2026 11:31 β€” πŸ‘ 655    πŸ” 113    πŸ’¬ 30    πŸ“Œ 28
From among long narrow bright green leaves grows a thin green stalk topped with a spectacular agapanthus blossom made of at least thirty individual flowers. The individual flowers have six blue petals with a purple stripe down the middle and several black-tipped purple stamens. (This blossom is unusual because all the other agapanthuses lost their flowers and set seed wees ago.)

From among long narrow bright green leaves grows a thin green stalk topped with a spectacular agapanthus blossom made of at least thirty individual flowers. The individual flowers have six blue petals with a purple stripe down the middle and several black-tipped purple stamens. (This blossom is unusual because all the other agapanthuses lost their flowers and set seed wees ago.)

#bloomscrolling

09.03.2026 23:00 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
From among long narrow bright green leaves grows a thin green stalk topped with a spectacular agapanthus blossom made of at least thirty individual flowers. The individual flowers have six blue petals with a purple stripe down the middle and several black-tipped purple stamens. (This blossom is unusual because all the other agapanthuses lost their flowers and set seed wees ago.)

From among long narrow bright green leaves grows a thin green stalk topped with a spectacular agapanthus blossom made of at least thirty individual flowers. The individual flowers have six blue petals with a purple stripe down the middle and several black-tipped purple stamens. (This blossom is unusual because all the other agapanthuses lost their flowers and set seed wees ago.)

#bloomscrolling

09.03.2026 23:00 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

Oh my God I hate driving.

09.03.2026 20:40 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Wordle 1,725 3/6.

1: Y Y Y b b …
2: b G Y Y b …
3: G G G G G …

When it takes you a long time to figure out Guess 3, you know there’s a high chance you’ll finish on Guess 3.

09.03.2026 18:45 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

In order to be on both the campuses I need to be on tomorrow, I have to drive to work and I am very grumpy about it. Also I forgot to take something home from work that I need so I have to drive *in the city* and I am even grumpier about it.

09.03.2026 10:38 β€” πŸ‘ 9    πŸ” 0    πŸ’¬ 0    πŸ“Œ 1

Wordle 1,724 5/6

1: b b b b G …
2: b b b b G …
3: b b G b G …
4: b G G G G …
5: G G G G G …

Five guesses is a long game to have no yellows! Also it’s as close to exactly half green as you can get with five guesses.

08.03.2026 18:58 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Very happy to have helped Will get one five thousandth closer to his goal for the number of books he wants to sell this year. He seems like a great guy, and I think he’s a good author.

08.03.2026 05:54 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
The cover of my copy of Rebel Gods, by Will Kostakis.
Under the title is a 3D maze with many stairs and arches and bridges drawn in gold and blue, with two women in off-the-shoulder dresses standing apart from each other.
Above the title are three teenagers: a boy has a plant growing out of his hands, another boy has a sword strapped to his back, and a girl has fire encasing her hands.

The cover of my copy of Rebel Gods, by Will Kostakis. Under the title is a 3D maze with many stairs and arches and bridges drawn in gold and blue, with two women in off-the-shoulder dresses standing apart from each other. Above the title are three teenagers: a boy has a plant growing out of his hands, another boy has a sword strapped to his back, and a girl has fire encasing her hands.

#read2026
Rebel Gods, by Will Kostakis
The creator gods imprisoned some of their children millenia ago and Connor, Locky and Sally have to deal with them escaping their prison. Suspenseful and funny and poignant, and a great conclusion to the story started in Monuments.

08.03.2026 05:53 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Wordle 1,723 6/6.

1: b G b b b …
2: b G Y b b …
3: b G b Y G …
4: G G b b G …
5: G G b b G …
6: G G G G G …

Decent bit of suspense there at Guess 5. Glad my instincts were right so that I got Guess 6 right.

07.03.2026 21:21 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I have read the Phantom Tollbooth aloud to my wife and to each of my daughters, and to my Year 7 class when I was their home room teacher.

07.03.2026 07:09 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

He had had a nasty feeling that that might be an idiotic thing to do, but he did it anyway, and sure enough it had turned out to be an idiotic thing to do. You live and learn. At any rate, you live. You also panic.

07.03.2026 07:02 β€” πŸ‘ 21    πŸ” 9    πŸ’¬ 0    πŸ“Œ 0

A single yellow balloon with a long white string drifts high in a bright blue sky.

07.03.2026 05:30 β€” πŸ‘ 0    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

A single yellow balloon with a long white string drifts high in a bright blue sky.

07.03.2026 05:30 β€” πŸ‘ 0    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

The nail salon is deserted, so the five nail technicians sit in a row with their elbows on the bench and their phones in both hands right in front of their faces.

07.03.2026 04:49 β€” πŸ‘ 0    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

The nail salon is deserted, so the five nail technicians sit in a row with their elbows on the bench and their phones in both hands right in front of their faces.

07.03.2026 04:49 β€” πŸ‘ 0    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

The fact that students can do the problem and not the interpreting in plain English says they are separate skills and need to be taught separately.

06.03.2026 20:54 β€” πŸ‘ 5    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I recommend this. Interpretation in context is the last bit of a long process and if they don’t finish the process they don’t get to it, so many of your students never get to it. Separating it and just doing the interpretation allows students the chance to practice that one skill they often miss.

06.03.2026 20:53 β€” πŸ‘ 5    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0