iiinova — where your digital self keeps evolving

Durtles @makeaproblem.bsky.social · 25/09/2026

October mail day is coming up for the Math Doodlers Club ( #snailmailclub for #math people.). Also remember that the July catch up mail is free for the month of September. #mailclub #mathsky #iteachmath #maths

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Durtles @makeaproblem.bsky.social · 09/09/2026

#mathdoodle: the connected lights problem - circle size 3 Full video: youtu.be/vlvTTe2Kp8o Mail Club subscription: ko-fi.com/makeaproblem... #math #maths #mathsky #iteachmath #mathdoodles #problemsolving #mathart

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Durtles @makeaproblem.bsky.social · 01/09/2026

Happy September! 🍎 It's back to school season, and my #math themed #mailclub is giving out copies of the July test run package for free for the month of September. Grab yours while supplies last because we don't restock. 😉 ko-fi.com/makeaproblem... #maths #mathsky #iteachmath #snailmailclub

An open envelope with an instruction sheet, a postcard, a piece of napkin, and a sticker.

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Durtles @makeaproblem.bsky.social · 26/08/2026

I sent my favourite #math problem to 4 #mailclub members Mail club subscription: ko-fi.com/makeaproblem... #maths #mathsky #iteachmath #snailmailclub

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Durtles @makeaproblem.bsky.social · 24/08/2026

3x4 cases of the path finding problem #mathdoodle full video: youtu.be/JjoNlyY2pdA math doodlers #mailclub: ko-fi.com/makeaproblem... #math #maths #mathsky #iteachmath #mathart #problemsolving

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Durtles @makeaproblem.bsky.social · 05/08/2026

My July stamp has a typo, and I didn't realize until after I finished packing. #snailmailclub #mailclub ko-fi.com/makeaproblem...

I didn't realize until after I finished packing the July test run of my snail mail club for math people,

that the July stamp has an "L" missing, so it says "Water Ilies" instead of "Water Lilies".

If you would like to see a "Water Ilies" stamp mark in your mailbox,

all the test run packages are now available as Catch Up Mail on my ko-fi page at makeaproblem/shop.
Link: www.ko-fi.com/makeaproblem/shop

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Durtles @makeaproblem.bsky.social · 28/07/2026

I cut the instruction sheets too wide in the test run for my snail mail club for math people, so I had to wrestle each and every envelope while packing. 😅 #snailmailclub #mailclub #math #maths #mathsky #iteachmath ko-fi.com/makeaproblem...

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Durtles @makeaproblem.bsky.social · 24/07/2026

Test run and sneak peek. Subscription link: ko-fi.com/makeaproblem... #snailmailclub #mailclub #math #maths #MathSky #iTeachMath

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Durtles @makeaproblem.bsky.social · 22/05/2026

f). A is the center of the sphere, and B is the midpoint of the radius. Where can we find point P on the sphere such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

A sphere with center at Point A, and Point B is the midpoint of a radius.

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Durtles @makeaproblem.bsky.social · 20/05/2026

A and B are on perpendicular radii CO and DO such that CA = AO and BD = 2OB. Where can we find point P on the circle such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

A circle with radii OC and OD that are perpendicular to each other. Point A is the midpoint of OC, and point B is on OD but closer to O than to D.

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Durtles @makeaproblem.bsky.social · 18/05/2026

d). E and B are the midpoints of perpendicular radii CO and DO. AE is the perpendicular bisectors of CO such that AE = CE. Where can we find point P on the circle such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

A circle with radius OC and OD that are perpendicular to each other. Point B is the midpoint of OD, and point E is the midpoint of OC. Point A is placed such that ABOE is a square.

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Durtles @makeaproblem.bsky.social · 16/05/2026

c). Point A and B divide radius CO into thirds. Where can we find point P on the circle such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

A circle with radius OC and points A and B are on OC, dividing it into thirds.

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Durtles @makeaproblem.bsky.social · 14/05/2026

b). Point A and B are on diameter CD such that CA = 2BD, and AB = 3BD. Where can we find point P on the circle such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

a circle with horizontal diameter CD. Point A is on CD and to the left of the center, and point B is on CD to the right of the center.

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Durtles @makeaproblem.bsky.social · 12/05/2026

This problem is inspired by the 1977 Canadian Math Olympiad Q2. a). Point A is the center of the circle, and point B is the midpoint of the radius it’s on. Where can we find point P on the circle such that ∠APB is the largest? #math #maths #ProblemSolving #iteachmath #mathsky

a circle with point A at the center and point B halfway between point A and the circumference of the circle.

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Durtles @makeaproblem.bsky.social · 08/05/2026

f). Is it possible to transform one of these figures into one of the others using only point sources? #math #maths #ProblemSolving #iteachmath #mathsky

Two green houses and two blue houses. The blue houses are mirror images of the green house, and the second pair of green and blue houses are horizontal stretches of the first pair.

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Durtles @makeaproblem.bsky.social · 06/05/2026

e). Find a set of point sources used to transform one of these similar figures into the other and identify the transformation(s) used. #math #maths #ProblemSolving #iteachmath #mathsky

A green house shape and an identical blue house shape moved half the shape's width to the right.

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Durtles @makeaproblem.bsky.social · 04/05/2026

d). Find the point source used to transform one of these similar figures into the other and identify the transformation(s) used. #math #maths #ProblemSolving #iteachmath #mathsky

A green house shape with a smaller blue house shape that's turned 45 degrees counter-clockwise and moved to the right.

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Durtles @makeaproblem.bsky.social · 02/05/2026

c). Find the point source used to transform one of these similar figures into the other and identify the transformation used. #math #maths #ProblemSolving #iteachmath #mathsky

a large blue house shape and a smaller green house shape that's the blue house rotated half way around the circle.

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Durtles @makeaproblem.bsky.social · 30/04/2026

b). Find the point source used to transform one of these similar figures into the other and identify the transformation used. #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 28/04/2026

This problem is inspired by the 1976 Canadian Math Olympiad, Q4. a). Find the point source used to transform one of these similar figures into the other and identify the transformation used. #math #maths #ProblemSolving #iteachmath #mathsky

A large blue house shape with a smaller green version of the same house shape inside.

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Durtles @makeaproblem.bsky.social · 24/04/2026

f). Find all the ways to write 81 as consecutive positive integers. #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 22/04/2026

e). Find two ways to write 12 as the sum of consecutive integers that have the same lists, similar to part d. #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 20/04/2026

d). Write 14 as the sum of 7 consecutive integers, and then write it as the sum of 4 consecutive integers. What do you notice about the lists? #math #maths #ProblemSolving #iteachmath #mathsky

On one line, 7 spaces added together to equal 14. On the second line, 4 spaces added together to equal 14.

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Durtles @makeaproblem.bsky.social · 18/04/2026

c). Which positive integers can be expressed as the sum of 6 consecutive positive integers? #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 16/04/2026

b). Which positive integers can be expressed as the sum of 5 consecutive positive integers? #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 14/04/2026

This problem is inspired by the 1976 Canadian Math Olympiad Q5. a). Which positive integers can be expressed as the sum of two consecutive positive integers? #math #maths #ProblemSolving #iteachmath #mathsky

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Durtles @makeaproblem.bsky.social · 10/04/2026

f). How many ways are there to walk along the grid lines from the front bottom left to the back top right without visiting any intersection more than once? #math #maths #ProblemSolving #iteachmath #mathsky

Three cubes arranged in an L shape with two in the front row and one in the back row on the right. Two green dots mark the front bottom left corner of the front row and the back top right corner of the back row.

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Durtles @makeaproblem.bsky.social · 08/04/2026

e). How many ways are there to walk along the grid lines from the bottom left to the top right without visiting any intersection more than once? #math #maths #ProblemSolving #iteachmath #mathsky

Four diagonally connected squares, with two in the top row, both connected to the one in the second row, which is connected to the square in the bottom left. Two green dots mark the bottom left and top right corners of the grid.

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