Celebrating 5 yrs since Building Thinking Classrooms in Mathematics, Grades K-12 was published! 🌍 The book has sparked a movement, been translated into 15 languages & inspired classrooms everywhere. Here’s to curious minds, thinking deeply and bravely! #btcthinks #iteachmath

This lesson uses a time lapse thermometer video as a context for discussing integer operations and absolute value. The video should provide some added meaning to the classic temperature drop problem. robertkaplinsky.com/work/te...

Want to challenge your Geometry students to find the area of triangles? Try out this Open Middle problem from Dan Wulf. www.openmiddle.com/area-of-...

Avoid this phrase if you don’t want to stigmatize the use of manipulatives in your math class. #math #teaching #btc

Interested in learning more about the FREE Polypad Virtual Manipulatives from @amplifyeducation.bsky.social? Sign up for the next Polypad webinar on Nov 5th at 7 PM ET. Even if you can’t make it, sign up to receive a link to the recording. tinyurl.com/5fb4m48z

Mathematics Tasks for the Thinking Classroom (6-12), @pgliljedahl.bsky.social & @webbkyle.bsky.social's new book, is shipping globally! ✅ 20 Non-Curricular Tasks ✅ 30 Curricular Tasks ✅ Tips for moving from page to practice Get discounts here: linktr.ee/btcthinks #thinkingclassrooms #btcthinks

The morning sessions on #RichMathTasks at #NSMTA2025 went great. Wonderful participation from everyone!

Math is figureoutable with @pwharris.bsky.social. lots of additive & multiplicative reasoning through problem strings to help us construct strategies, models, and concepts. @nsmta.bsky.social #NSMTA2025

Looking forward to presenting tomorrow on #MathRichTasks at #NSMTA2025.

Kelly Power, presenting on Creating Leveled Assessments at #NSMTA2025.

Tomorrow is the day! The #NSMTA2025 conference will bring together 800 mathematics teachers from across Nova Scotia. A great day to connect, learn and share. #ITeachMath

Have you seen #ObserveMe but want to learn more? Check out these links: What it is: robertkaplinsky.com/observeme Ignite talk on it: robertkaplinsky.com/observe... Interviews with teachers: robertkaplinsky.com/tag/obs... Pro tips: robertkaplinsky.com/trouble...

Can your high school students create a parallelogram, triangle, or rectangle by listing their points when given one? Find out using these three Open Middle problem from Bryan Anderson. www.openmiddle.com/creating... www.openmiddle.com/creating... www.openmiddle.com/creating...

[New Post] Ontario Math Links - My favourite #math related links from this week: ontariomath.blogspot.com/2025/10/math... Links and help from @howiehua.bsky.social @looneymath.bsky.social @mnmmath.bsky.social @abeljennifer.bsky.social @benjamindickman.bsky.social &more #MathChat #MTBoS #iTeachMath

After watching our book ship worldwide, my own copies finally landed. Surreal to say the least! So excited about what @pgliljedahl.bsky.social and I created, and even moreso to get this into the hands of teachers! #buildingthinkingclassrooms @btcthinks.bsky.social

✈️ Heading to NCTM? I’m honored to be presenting again this year! 📅 Thursday, 2:30 PM 🎯 Session Title: Early Algebraic Thinking with Desmos Classroom Here’s a short preview of the ideas we’ll discuss: kurtsalisbury.substack.com/p/when-does-... #mtbos #math @amplifyeducation.bsky.social

Just submitted a session proposal for OAME 2026. Looking forward to this always fantastic conference. #ITeachMath

Join us in Moncton NB for the 2026 Building Thinking Classrooms Regional Conference with @peterliljedahl.bsky.social @btcthinks.bsky.social July 6–7, 2026! 🧠📚 💡 Discover practical strategies to spark deep thinking in your classroom 📩 Sign up for updates: tinyurl.com/yc6cfbzk

Look what arrived! Just when you thought the K-5 book was big, the 6-12 is even thicker! I've been through it already and wow—peterliljedahl.bsky.social and @webbkyle.bsky.social really delivered. You want this. 🔥

TODAY'S THE DAY! It's one of the coolest dates of our lifetime. Whether you go by month/day/year or day/month/year, if we write the date as one number, we will get a square number! Both sides can agree that today's date is a square date. 9,272,025=3045² 27,092,025=5205²

At NCTM 2025 Annual Meeting & Exposition, we’re showing how BTC & ICUCARE transform math for learners who’ve been left out. 📢Empowering Marginalized Learners in Mathematics 📅 Oct 18 | 8 AM | Georgia World Congress Center With Dr. Peter Liljedahl 🔗 www.nctm.org/atlanta2025/... #NCTM2025 #NCTMATL25

Proofing #SubtractionbyHeart! The new cards are looking lovely :-) We should have these out by early 2026! #iteachmath #mtbos

I'm excited to present a free webinar on September 30. Register here: heinemann.zoom.us/webinar/regi...

Did you know that we can visually see why sqrt(40)=2sqrt(10)? Let's see how we can visualize rewriting square roots!

🚨 Registration is OPEN for the Building Thinking Classrooms online workshop w/ @pgliljedahl.bsky.social via @grassrootsworkshops.com! 🧠 6 modules packed videos, strategies & real examples to get students collaborating & thinking deeply. 👉 Register by Oct 3 grassrootsworkshops.com/workshops/bu...

Such a great conversation with @peterliljedahl.bsky.social & @mikeflynn55.bsky.social on what has changed since the orange book. Lots of great dialogue on the closing & building rubrics early. All these ideas will be here ➡️https://grassrootsworkshops.com/workshops/building-thinking-classrooms

Visual Patterns 🤝 Pattern Blocks I am currently OBSESSED, in a (mostly) healthy way, with @fawnnguyen.substack.com visual patterns and @mathforlove.bsky.social pattern blocks for kids to learn and create patterns. Ah-may-zing. Also, I am in LOVE with Mary Vail's Thinking Desks, they are phenomenal!

Can your high school students create a parallelogram, triangle, or rectangle by listing their points when given one? Find out using these three Open Middle problem from Bryan Anderson. www.openmiddle.com/creating... www.openmiddle.com/creating... www.openmiddle.com/creating...

Create a number where the sum of the digits is a multiple of 9. It is guaranteed that the number you created is a multiple of 9. Here's why this will always work:

So excited for the workshop to launch. There are so many new ideas shared as well as new ways to see the ideas that were presented in the books. #buildingthinkingclassrooms

Sometimes you stand on the furniture when creating a Thinking Classroom with a room full of families! #theanswersare #buildingthinkingclassrooms #iteachmath As Peter says, “The furniture moves.” But sometimes there’s no where for it to go! 🤣

Here are three reasons I think all math educators should use social media to improve professionally. robertkaplinsky.com/3-reaso...

My latest newsletter! Check it out: drive.google.com/file/d/1nxRu...

Registration for grassrootsworkshops.com/workshops/bu... opens up this Friday, September 19th! We are super excited to share this video-based, self paced workshop with you! #btcthinks @peterliljedahl.bsky.social @robertkaplinsky.com @mikeflynn55.bsky.social @btcthinks.bsky.social

Check out the professional development options on Grassroots Workshops (@grassrootsworkshops.com‬). There are flexible online workshops on topics including mathematics, social justice, teaching online, coding, English, wellness, and science. grassrootsworkshops.com/

Want to help students develop conceptual understanding of parabolas? This lesson uses the game Angry Birds as a context for understanding what information you need to graph a quadratic. robertkaplinsky.com/work/an...

A wonderful learning day in PSSD about Spiraling Your Math Curriculum. Always happy to have access to @wipebook.bsky.social for our thinking tasks & collaboration time! @pstateachers.bsky.social

Peter Liljedahl and Mike Flynn will be hosting a live webinar about #BTCthinks. Join Peter, Mike and classroom educators on Sept. 18 at 5:00 PM PST for a live conversation. Registration is FREE for anyone to attend! Register here: www.buildingthinkingclassrooms.com/webinar #MTBoS #iteachmath

Did you know that Hyundai offers a 100,000 mile in countries that use miles and 100,000 km warranty in countries that use the metric system? Are they the same? If not, which is better for the consumer and which is better for Hyundai? robertkaplinsky.com/work/ca...

A thing I made back in 2017. Twelve pyramids joined together in two zigzags roll up into two cubes and one silver rhombic dodecahedron.

Thanks to all the participants in my Rich Task and AI Workshop today at #ITCamp2025. So much wonderful learning! @wipebook.bsky.social #hrcemath

The penultimate week of #MathPhoto25 is #circles! Where do you notice circles, cylinders, spheres or ellipses in the world around you? #ITeachMath #MathsToday

Go from wondering about how to use open questions in math instruction to confidently creating your own or adapting ones you find. Learn more about Marian Small's How To Create And Use Open Questions In Math Class online workshop at grassrootsworkshops.com/wor...

I've heard lots of great ideas in presentations, but I often need more time to think about an idea, try it out, and learn more. That's why I made my six-week online workshop to help teach math through problem solving. Learn more at: https://robertkaplinsky.com/eps/

Playing Mastermind with my 6 year old inspired me to make this in #Desmos. I discovered I'm a lot worse at guessing than I thought! #MTBoS #iteachmath classroom.amplify.com/activity/687...

Can your high school students create a parallelogram, triangle, or rectangle by listing their points when given one? Find out using these three Open Middle problem from Bryan Anderson. www.openmiddle.com/creating... www.openmiddle.com/creating... www.openmiddle.com/creating...

ICYMI, Math Tasks for the Thinking Classroom, Grades 6-12 (aka "the burgundy book") is available for preorder! US customers: Pre-order from Corwin.com and use code SAVE20 to receive 20% off! Canadian customers: Pre-order from University of Toronto Press (t.ly/WVNCg) with code TASKS20 for 20% off!

Vancouver!📣 I’m hosting a laid-back Choosing To See Book Tour coffee meet-up on July 7 — come connect, sip ☕, and chat about student-centered learning. 📍 We Bake Cafe, 9630 Cameron Street, Burnaby, BC | 🕖 5-6 PM 🔗 RSVP: sedaeducationalconsulting.com/events-1 #Choosing2See #ICUCARE #dbc_inc