## Friday, January 26, 2018

### Math Links for Week Ending Jan. 26th, 2018

I have mentioned Math Is Visual before. It's creator @mathletepearce continues to try to visualize math concepts to help students understand basic concepts better. Recently he's been working on visualizing integer operations and has created this playlist that walks through basic addition and works it's way to more complex subtraction. He really takes the visual aspect seriously and you should to. But for optimal results, you really have to go through the entire playlist in order to get the benefit. Stepping in in the middle could disrupt the flow from the purely visual to the mathematical symbolic. Each video has it's own page that goes into much more detail on some of the teacher moves you might use.
Curriculum Tags: Gr7, Gr8
http://mathisvisual.com/series/integers/

I have released a couple of new Desmos Activities this week. The first deals with projectile motion. It starts with some investigation of launch angle, speed and height and then offers up some challenges. Finally it ends with a 'sandbox' for kids to play and experiment in.
Curriculum Tags: MCR3U, MCF3M, MBF3C
http://engaging-math.blogspot.ca/p/desmos-activities_10.html

The second is a pair of activities dealing with parabola transformations. The first is on translations and the second is on stretches. Along the way there are tables to complete, characteristics to describe, marbleslides to solve and a randomly generated page of equations to match with a graph.
Curriculum Tags: MPM2D, MBF3C
http://engaging-math.blogspot.ca/p/desmos-activities_10.html

It looks like @MrOrr_Geek has been working overtime to help you in your math class. In this post he explores some of the best ways you can use two truths and a lie in math class. He describes them in the video and gives you a downloadable user guide. So what are you waiting for?
Curriculum Tags: All
http://mrorr-isageek.com/4-ways-to-use-two-truths-one-lie-in-any-math-class/

Do you want your kids to work on their basic number sense but in a puzzly kind of way. Then consider having them deal with partitioning numbers (eg 4 can be 4, 3 and 1, 2 and 2, 2 and 1 and 1, or 1 & 1 & 1 & 1). Via @MathforLove
Curriculum Tags: All
http://www.thehindu.com/children/partitions-and-pieces-of-eight/article22489606.ece

Leave it to @ddmeyer to come up with a way to make the Interwebs more welcoming. A while back he started to search the Twittersphere for math teachers who Tweeted and were either new to Twitter or had no interactions. Well now he is enlisting the rest of us to do the same. He has started a new site: Lonely Math Teachers where he has scraped Twitter to find math tweets with low interaction and is asking us to interact with them. Nicely done. Check it out.
Curriculum Tags: All

"Why we don't cross multiply" - that's the title of a post from @K8Nowak and what follows is a fairly thorough description as to why introducing cross multiplication too soon (or at all) is a problem developmentally for students.
"I know that lots of people are very comfortable teaching cross multiplying, and this change is challenging."
It is uncomfortable for many teachers because that is what we learned as students. But she has some ideas as to how to pull the math off without going directly to cross multiplication.
Curriculum Tags: All

A very surprising result in the car crash analysis video from @numberphile. Some good math in there with working with formulas with powers as well.
Curriculum Tags: MPM1D, MFM1P

This is a neat little problem that deals with perfect squares.
Curriculum Tags: gr7

This is so fun. How do you create a 3 sided coin? Watch and find out. Along the way you'll see some geometry and some probability theory dealing with the binomial theorem and the normal distribution along the way.
Curriculum Tags: MDM4U

How about some composite functions? Thanks to @mathtans for pointing this one out.
Curriculum Tags: MCR3U

## Friday, January 19, 2018

### Math Links for Week Ending Jan. 19th, 2018

For some teachers, having a clear and exact plan when executing a lesson is very important. For others, they fly by the seat of their pant. If you are part of the former, then you might like this new-ish feature from @Desmos where you can get a teacher guide for any activity (theirs, yours, or someone else's). The guide, has checklists, screenshots, teacher notes and a place for your own notes. To access the guide just click on the Teacher Guide button that appears on each Desmos activity now (even ones you made yourself). Read about it at the link below and then check it out yourself.
Curriculum Tags: All
http://blog.desmos.com/post/169633045802/friday-fave-for-january-12

I have always been a fan of the area formula for a trapezoid. Why? because it's often dismissed but it can actually be used to determine the area of a parallelogram, rhombus, rectangle, square and even a triangle. So I made this demo sketch that basically shows the calculations using the trapezoid formula and the traditional formula for each shape. And it's dynamic so you can drag the points to see the calculations change in real time.
Curriculum Tags: Gr7
http://engaging-math.blogspot.ca/p/web-sketches.html

Do you want a fun way to talk about unit rates? Then you might find this @desmos activity called Click Battle. I like how it starts with students seeing how fast they can click and that's the hook to helping them use and understand unit rate.
Curriculum Tags: Gr8, MPM1D, MFM1P, MAT1L, MAT2L
http://blog.desmos.com/post/169360063287/friday-fave-for-january-5

If you are a user of the @OnMathies tools then you know that they are continually improving them. One new improvement is that you now have the ability to save documents in the NotePad app. This is helpful if you want to create stuff ahead of time to use in class or for your students to open and play with.
Curriculum Tags: All
http://mathies.ca/learningTools.php#Nn0

In grade 8 in Ontario we are supposed to classify quadrilaterals by their diagonal characteristics. This quadrilateral card sort from @theshauncarter could be a nice way to bring some prior knowledge up when starting that lesson.
Curriculum Tags: Gr8

Looking for some tips on how to become more productive in your teaching? Then check out @MrOrr_Geek's post on his top 10 tools. Watch the video and then read the post for more details.
Curriculum Tags: All
http://mrorr-isageek.com/10-tools-in-my-teaching-day/

I have probably posted this picture before but this is the first time that I have seen this version. The annotation is done by the company who built the ramps. If you want to see video of the actual jump, click here.
Curriculum Tags: MPM2D, MFM2P, MCF3M, MBF3C, MCR3U
https://ctconstructions.wordpress.com/ctconstructions/

A nice problem for geometry from @LauraWheeler
Curriculum Tags: MPM2D, MFM2P

## Friday, January 12, 2018

### Math Links for Week Ending Jan. 12th, 2018

Find out about mathematician @lewlefton who is also a stand up comedian (with math jokes) and @TheMathGuru who talks about her first day as a student teacher (and hails from Toronto).
Curriculum Tags: All

If you are talking about simulations then you might want your kids to try this one out from @vihartvihart and @ncasenmare where they use polygons who are happy or sad to simulate why segregation happens.
Curriculum Tags: MDM4U
http://ncase.me/polygons/

If you are at all thinking of using visibly random groups in your class, one thing that might hold you back is getting started. Sure you get the kids into random groups but how do you keep control? Why not give them a non math related starter so they won't be shy about talking to each other with a purpose. So to help you @LauraWheeler has compiled her 90 Getting to Know You questions. So you now have one less excuse to get started.
Curriculum Tags: All
https://mslwheeler.wordpress.com/2018/01/11/90-days-of-getting-to-know-you-questions-for-visibly-random-groups-%F0%9F%A4%94thinkingclassroom/

Some posts on medium from @mathgarden and @JamesTanton on why the current system of education is failing our students. The thread there is that math class can be a lot more enjoyable for students than it is right now and we can do it while still providing a quality math instruction.
Curriculum Tags: All
https://medium.com/q-e-d/its-time-to-let-go-of-antiquated-edicts-in-the-mathematics-classroom-8629d139a751
https://medium.com/@sunilsingh_42118/back-to-basics-mathematics-movement-re-imagining-the-classroom-as-a-sweatshop-with-victorian-24fc635ba599

And along the same lines and also highlighted at Medium is @MathewOldridges essay on the importance of play along with your math classes. Watch the video and then read the essay.
Curriculum Tags: All
https://medium.com/q-e-d/math-is-play-or-at-least-it-could-be-more-playful-cbd856d92aab

If you are in the beginnings combinatorics then why not start with something simple that students might relate to from @MathBeforeBed and while you are there check out the other math starters
Curriculum Tags: MDM4U
https://mathbeforebed.com/2018/01/09/the-doc-is-in/

Are you new to 3 Act Tasks? Or perhaps helping someone get started? Then you might like this Sketchnote from @LauraWheeler to summarize the main points (and some useful links in the post as well)
Curriculum Tags: All
https://mslwheeler.wordpress.com/2018/01/12/3-act-math-sketchnote/

## Friday, January 5, 2018

### Math Links for Week Ending Jan. 5th, 2018

I always like when you can find a real world example of where math can help you out. In this case it's this recently released picture from NASA. It's unique because it is of the earth and the moon in the same shot. So you really get a sense the scale of, not only the distance between the two, but the relative sizes. So where's the math? Using some sine and cosine law you can verify the distance between the two and get a better idea of why the image looks the way it does (with the moon seeming smaller than it should be).
Curriculum Tags: MCR3U, MCF3M, MAP4C
https://qz.com/1170202/how-far-is-the-earth-from-the-moon-nasa-spacecraft-captures-the-true-distance/

Though these have been around for a while, these are all the multiplying binomial dynamic websketches in one place. Great for visually representing, practicing and gamifying from @dpscher
Curriculum tags: MPM2D, MFM2P, MCF3M, MCR3U, MBF3C
http://www.sineofthetimes.org/binomial-multiplication-and-factoring-games/

Hey, there's a new prime number and it's 23 million digits long.
Curriculum Tags: All
https://fivethirtyeight.com/features/we-have-a-new-prime-number-and-its-23-million-digits-long/

Some neat math here on the frequency of the sound of a champagne cork popping. By recording and visualizing the sound waves they are able to get the frequency and visually see the vibrations. Great for MHF4U in talking about combination of sinusoidal functions as well as just plane old frequency measuring.
Curriculum Tags: MCR3U, MHF4U
https://youtu.be/xTcvl-kw9fU

It's cold out there and the calculation to determine the temperature when considering the wind chill is a complicated mess with decimal powers but it would be a great exercise for students to model the temp at different wind chills. Via @RMByrne
Curriculum Tags: MCR3U, MHF4U
http://www.freetech4teachers.com/2018/01/how-is-wind-chill-calculated.html

Some images for the new year. First a puzzle from @IJTANEJA
Curriculum Tags: All
https://inderjtaneja.com/2017/12/31/2018-upside-down-with-digits-0-1-6-and-9/

And then of course, this classic
Curriculum Tags: MCV4U