Erick Lee

A 2L bucket is filled with Halloween candy... how many pieces of candy are there?

The first two of six clues are revealed. Clue #1 - the answer is a three digit number. Clue #2 - The answer is an even number.

Halloween is just around the corner. I made a Halloween treat esti-mystery to share with students. #ITeachMath docs.google.com/presentation...

Apply now to be a presenter at OAME 2026 - Let’s Talk Math. We are looking for diverse session proposals under the following themes:
Let’s talk equity
Let’s talk assessment
Let’s talk technology
Let’s talk content
Let’s talk pedagogy
We would love to have you!!!! bit.ly/callforproposals2026

Has rotational or reflective symmetry. Concave/convex. All straight sides (polygon) or non-straight sides (eg circle).

We know ball. And okhsv, oklab, and oklch. 🎨

📝 Learn more about new custom color functions in the Desmos Help Center: help.desmos.com/hc/en-us/art...

An engaging narrative. Check out this review. aperiodical.com/2025/08/revi...

Use 9 different factors of 198 in a 3 by 3 grid. The numbers in the top row add to 39. The numbers in the middle row add to 119. The numbers in the bottom row add to 13. The numbers in the left column add to 14. The numbers in the middle column add to 33. The numbers in the right column add to 124.

Start your week with this #yohaku. Fill in cells with 9 different factors of 198 to get totals shown in each row/column. #mathsky #iTeachMath

[New Post] Ontario Math Links-My favourite #math related links from this week:

ontariomath.blogspot.com/2025/10/math...

Links&help from @howiehua.bsky.social @karencampe.bsky.social @quantamagazine.bsky.social @dawndelvecchio.bsky.social @calarmstrong.bsky.social &more #MathChat #MTBoS #iTeachMath

A-level Maths task on finding the remainder when dividing a polynomial by a linear expression using algebraic long division.

A-level Maths task on shading regions in two dimensions divided by linear and quadratic inequalities.

A-level Maths tasks on (i) solving linear and quadratic inequalities graphically, and (ii) simplifying algebraic fractions either by splitting the fraction or by factorising.

✨New A-level resources from this week's Year 12 lessons on graphical inequalities, algebraic fractions and algebraic division. The new A-level section is slowly growing! www.draustinmaths.com/a-level
#MathsToday #ALevelMaths #UKMathsChat

A quick bit of #Maths in #Museums: The shape of castles and their keeps and towers.

tommaths.blogspot.com/2025/10/math...

#MathsToday #MuseumEd

October Calendar Problems October is here, and with it the crisp fall air here in the northeast US. No matter where you are, you can get a breath of fresh air with some problem solving in your math classes! Here is the 2015…

October is here & so is the next month's #ProblemSolving calendar!

Share your thinking (& your students' thinking) here or on the post.
#MTBoS #iTeachMath #T3Learns #RecreationalMath #MathsToday

karendcampe.wordpress.com/2025/10/01/o...

#Mathstoday
Year 10 found expressions for shaded areas.
Made this last year for an extension but it was nice spending a bit longer on it.

[New Post] Ontario Math Links - My favourite #math related links from this week:

ontariomath.blogspot.com/2025/09/math...

Links and help from @diffgeom.com @robertkaplinsky.com @howiehua.bsky.social @edutopia.org @jennalaib.bsky.social and more #MathChat #MTBoS #iTeachMath

A parquet deformation based on squares. Created in Excel and Krita.

I was calling this geometric fade but I learned it is actually called parquet deformation.

There are over 1500 distinct activities on the Transum Mathematics web site. However you'll be pleased to know that there is a search page. It's not AI so works best when you use just one or two words.

www.transum.org/Search_Form....

Hope you find what you need.

#maths #mathschat #mathstoday

Series of questions on domains of various functions

This is always a fun day in precalc - lots of friendly arguments

A box of marbles. Students estimate the number of marbles with binary numbers. 5 clues are given, one at a time, for students to revise their estimate.

Created a binary number esti-mystery. Students practicing powers by working with binary and base 10 number conversions. The final clue is a bit of a giveaway. Check out this site for lots of examples: stevewyborney.com/category/est... #ITeachMath #MathsToday

Would you rather have $200 or a stack of quarters as tall as you?

Measurements taken. Happy Equinox!

Really disappointed that I can't make measurements for today's #equinox. But that doesn't mean you can't!

Solar noon is in about an hour and half for the Eastern time zone. I'd love to see you participate!

sites.google.com/view/themeas...

[New Post] Ontario Math Links - My favourite #math related links from this week:

ontariomath.blogspot.com/2025/09/math...

Links and help from @mathsjem.bsky.social @edutopia.org @howiehua.bsky.social @murrayh83.bsky.social #MathChat #MTBoS #iTeachMath

(Filing cabinets lined up in a row at the side of the road.)

The best way for a photo to catch my attention is if it looks like data.

Fig. 1. Bar plot displaying amount of storage per filing cabinet.

Handrail casting zigzag lines on cement stairs. Green grass grows in the corners and green mildew stains the cement.

#BlueSkyArtShow #Angles #AlphabetChallenge #WeekLforLines #ColorADay #GreenSat #SaturdayStairs #StripesOnSaturday

Zigzag escalation - 2025

#Phonetography
#EastCoastKin #ArtYear #handrailsteps #clinginglife #pointy

The Mathematicians’ Library by Thomas Briggs

My copy of The Mathematicians’ Library arrived! A medley of my favourite topics: mathematics, books and history. Really enjoying it so far. @teakayb.mathsy.space

Lines of tiles, vents, and wood along edge of swimming pool

#AlphabetChallenge #WeekLforLines

Statistics Supplied is a great exercise for deepening students' understanding of mean, median, mode and range. It's the reverse of the traditional exercise.

Have a go at the first few questions yourself!

www.transum.org/Intro/?ID=1114

#mathsresources #mathschat #mathstoday #mathchat

Play with your Problems I am a compulsive problem poser. When presented with a mathematical context, I have an incredible amount of difficulty leaving it alone. My teacher instinct is to push, prod, tinker, and/or alter i…

I wrote a new post yesterday:

natbanting.com/play-with-yo...

It’s about the benefits of teachers tinkering with the problems/prompts we offer students.

(And, tangentially, about the benefits of conference spaces where we are given license to do so)

#iteachmath

Looking to get kids arguing about math? Check out www.wouldyourathermath.com/ from John Stevens. There are so many great "Would you rather..." scenarios!

Want more support using them with your students? Check out his online workshop here: grassrootsworkshops.com/wor...

Promised to be better at doing a daily #mathstoday and this is my first post of the term. 🤦🏻‍♀️
Rolled out a Durham Maths Mystery to practice algebra with Y8, they loved it. Lots of resilience. 💪🏻
These resources are 20 years old and I forget they exist, rediscover them & love them all over again.

The Mathematicians’ Library: The Books That Unlocked the Power of Numbers Far from an academic "maths book", it is a book about maths; about the role that this most ancient of human endeavours has played in the development of humanity, and where its achievements have prompted - and been prompted by - growth in disciplines that many people in the modern world see as entirely separate. [cat_tail]

The Mathematicians' Library is out TODAY in all good bookshops and libraries, and direct from me if you'd like a signed copy.

Ideal School Supply Co Ingento paper cutter.

Ideal School Supply Co Ingento No. 5

New Teacher Pro Tip: the best paper cutter in the school is probably the oldest one. This Ingento in the second floor staff room is probably older than I am but cuts beautifully. #ITeachMath