## Friday, January 29, 2016

### Math Links for Week Ending Jan. 29, 2016

In the last few weeks I have come across some great conversations on Twitter. This week was no different. In this case @MrOrr_Geek posts the kernel of an idea: given a quadratic, give two truths and a lie.
He gets some suggestions and then creates a post about this simple exam review strategy. Though this particular example is dealing with quadratics, you could easily see how any topic could be done this way. In fact, in the blog post he does it with a rational function and his grade 12 class (and really doesn't need to be limited to an exam review).
Curriculum Tags: MPM2D, MFM2P, MCR3U, MCF3M, MBF3C. MHF4U
http://mrorr-isageek.com/better-questions-two-truths-one-lie/

I have always liked doing this activity with my data management students where I asked them to go home and find two magazines then determine the total number pages, number of pages with ads on them and the cost. They all bring that data in and it builds a nice rich dataset. You can do one and two variable analysis with it. And thanks to Google Forms, collecting that data has become even easier. So there are well over 200 pieces of data in the set now.
Curriculum Tags: MDM4U
http://found-data.blogspot.ca/2016/01/magazines.html

Another nice review strategy from @MrOrr_Geek. Though this comes from his Advanced Functions class, it is another strategy that could be applied to just about anything (as long as answers come out to numbers). Put the kids in groups, give each group a set of problems then write the sum of each groups question on the board. If they get the same sum then they know they did their questions right, if not then they have to re-check (BTW, I love that kids are writing their solutions with dry erase markers on their desks).
Curriculum Tags: All
http://mrorr-isageek.com/sum-it-up/

When ever I used to teach combinatorics I wouldn't miss talking about lotteries and specifically those like the 6/49 or the Powerball. Invariably we would talk about being able to buy all the possible combinations and what that would take. It was pretty quickly determined that you would need a huge effort or at least some sort of automation (much like Lazlo had if you have ever seen the movie Real Genius). Well, as it turns out, somebody has actually done this. They filled out and played every combination. Listen to this Planet Money story to find out how.
Curriculum Tags: MDM4U
http://www.npr.org/sections/money/2016/01/13/462982983/10-11-51-52-62-18

Another recent story from Planet Money is about the fact that many psychological studies are actually not repeatable. When talking about data management we often talk about bias and this episode talks about how bias could be why some of these studies are not repeatable.
Curriculum Tags: MDM4U
http://www.npr.org/sections/money/2016/01/15/463237871/episode-677-the-experiment-experiment

I think @MaryBourassa has touched on an interesting point in a very short post she made recently:
"I don't know if it's just me, but I find it difficult at the end of the semester to give appropriate wait time when giving individual help. I will ask a question and want to jump in with the answer or will want to just tell them how to start a question rather than asking a question to get them to think about what they should be doing."
I think many of us became teachers because we like that warm feeling of imparting knowledge. Traditionally that has come in the form of us telling students about math rather then letting them struggle to get there but us telling students all the time is very passive for students. They need to be active learners in order for that information to stick. Let Mary know how you feel about this on her blog.
Curriculum Tags: All
http://marybourassa.blogspot.ca/2016/01/mpm2d-day-78.html?m=1

If you are talking about patterns then it is always neat when you can talk about an interesting pattern. In this case, take a whole number and follow the pattern: if it is an even number, n, then the next term is n/2 and if it is an odd number then the next term is 3n + 1. It is pretty simple but the interesting thing is that no matter what the starting point, it will always reach one. Thanks to Mark Esping for this one.
Curriculum Tags: Gr7, Gr8

As it turns out there are many videos like this one, thanks to the iPhone. I like it because when are talking about combining functions in MHF4U I have always liked to show that sound waves were made from simpler sine waves. I would get an oscilloscope and wave generator from the science dept and show it. Now all I need is a phone and a guitar (or this video). Thanks to Mark Garant for this one
Curriculum Tags: MHF4U

Some good @Desmos videos on how to use the Teacher.Desmos.com site. Do you want to get started and aren't sure how? Start here
Curriculum Tags: All

It's always nice when you can bring data into the class that might be interesting to students. Here we have data to suggest that the number of words that Disney princesses have spoken has become less and less over time. Check the site out for a video and more data
Curriculum Tags: Gr7, Gr8, MDM4U
https://www.washingtonpost.com/news/wonk/wp/2016/01/25/researchers-have-discovered-a-major-problem-with-the-little-mermaid-and-other-disney-movies/
A recent theme of the MTBoS Blogging Initiative was "My Favourite". I like this simple way to pique student's interests to start this problem from @jgibson314.
Curriculum Tags: Gr7, Gr8, MFM1P
http://jgibson314.blogspot.ca/2016/01/my-favourite-problem.html

Do you want a fun way to look at order of operations? Try this limerick. Thanks to Michele Cooper for this one
Curriculum Tags: Gr7, Gr8

## Friday, January 22, 2016

### Math Links for Week Ending Jan 22, 2016

Last weekend I noticed someone had tweeted out a link to a recent Ontario Math Links. Upon closer scrutiny it wasn't a "someone" but instead a "something". The tweet came from @MTBoS_Blogbot. That is, it is an automated bot that searches MTBoS blogs and tweets out when ever there is a new post on them. The bot was developed by @Lustomatical using code that can be found here and the MTBoS blogroll found here. So never miss another MTBoS blog post, and just follow @MTBoS_Blogbot
Curriculum Tags: All
So for Christmas we got a Keurig which is odd because I don't really drink hot beverages (turns out my son does) and now we have all these K-Cups lying around. My wife insists she can use them for something educational. Low and behold, you can. Just take a look at this page from @cherandpete and you will think you hit the K-cup jackpot. To get a sense, watch the video below and then check out the link to see the math-ness.
Curriculum Tags: Gr7, Gr8
https://mrcssharesease.wordpress.com/k-cups-4-classrooms/

It really is too hard to keep track of all of the teacher made Desmos activities but it is worth it to point out some of them. This one from @RobertKaplinski came out of @K8Nowaks post about simple basic concepts and I love it. It's a Polygraph on plotting points. Really simple and something that typically is not very engaging to students but doing it this way gives a little toward the engagement factor.
Curriculum Tags: Gr7, Gr8
https://teacher.desmos.com/polygraph/custom/560aa8df9e65da561507a5ce

In Data Management, one of the topics is bias in collecting and analyzing data. Here is a nice @SciFri podcast that starts out talking about computers that do the work of sifting through resumes and branches out into many different examples of bias seen with big data. Some good information for your students. Listen here.
Curriculum Tags: MDM4U
http://www.sciencefriday.com/segments/why-machines-discriminate-and-how-to-fix-them/

If you are a fan of the Flipped classroom model then you know how much time it takes to create enough videos to make it work. You can sometimes resort to other people's videos (there are tonnes) but that may not match what you are doing. Well if you are in Ontario and use some of the current textbooks then there is a huge resource (literally 1000s of videos) that cover many of the questions in those books. Though not all books are covered and not every question is done, there is more than you could really use. @mglMin has created a huge resource that you can subscribe to and can be customized for your Ontario school. Check out the books available for the courses in the Academic/University stream at the link and don't miss the bonus videos on Canadian Math competitions.
Curriculum Tags: MPM1D, MPM2D, MCR3U, MHF4U, MCV4U, MDM4U
http://prepanywhere.com/

Last week in a conversation I Tweeted out a comment about assessment not being a very sexy topic and @DonFraser9 replied asking what the sexy topics were
We mentioned some things like 21st century learning, Growth Mindset, Student engagement etc. Then I saw this post from @K8Nowak about the "non sexy" topics in math class. The basic questions and why we should value them. It's a good read about that everyday stuff that is still important. And as a bonus, she has some great links on first differences, plotting points (see above), degrees and radians and more. Thanks to @Wheeler_Laura for pointing this one out
http://function-of-time.blogspot.ca/2016/01/in-defense-of-unsexy.html

Hey, we got a new prime number this week. A couple of videos from @standupmaths. The first is from his own channel
Curriculum Tags:All

And the second one on the @Numberphile channel
Curriculum Tags: All

I was at the grocery story and saw this. So much patterning that can be done with this. Series and sequence too. First question that comes to mind is do each of the piles have the same number of apples?
Curriculum Tags: Gr7, Gr8, MPM1D, MFM1P, MCR3U
https://www.instagram.com/p/BA0QUksx6yc/
A photo posted by David Petro (@lookimyourfather) on

Very cool fractal gif
Curriculum Tags: All

## Saturday, January 16, 2016

### Math Links for Week Ending Jan. 15, 2016

"I witnessed more risk-taking from my students, more passion for learning, creativity, and a more active math talk community." - Amy Lin
That is what @amylin1962 concluded when she stopped giving out marks in her grade 9 math class this year. I really like the idea of no marks but recognize that it's a very gutsy move. Giving marks is so ingrained into the educational framework, that it takes extreme conviction and understanding of assessment to pull it off. But based on her story it seems like she is well on her way. The research says that if we look at the three choices of giving marks alone, giving marks and written comments or just giving comments, there is no added benefit for students if you give marks and comments (they often ignore the comments and focus on the marks) but if you only give comments then that does the most in moving students forward in their thinking. And if that is truly our goal, to move student thinking forward then trying what Amy did this year is a step in the right direction. Read about her journey and how she had her students come up with their own grades at the link below.
Curriculum Tags: All

Forget that it's a new way to slice a pizza. Instead consider the very cool tessellation that occurs here. I think it's a really neat way to show that you can do tiling with complex shapes. Thanks to @mathletepearce and Michael Lieff for this one.
Curriculum Tags: Gr7, Gr8
http://gizmodo.com/mathematicians-have-found-crazy-new-ways-to-cut-pizza-i-1751776752

Again, the fun and power of Twitter is shown when @marybourassa tweets about a question dealing with the ambiguous case. Then Twitter responds including @mikeandallie (if you haven't seen his videos on doing math with his kids then you are missing out). He finds a connection to a theorem dealing with angle bisectors. So Fun.
Curriculum Tags: MCR3U
https://mikesmathpage.wordpress.com/2016/01/09/a-fun-connection-with-mary-bourassas-problem/

I love when you can show the power of data in places you might not expect. In this case it's farming. For the average person, the amount of data that is used in current farming practices would be surprising but when I ask my farmer friends about it they say that using data is old news. None the less this is a great snapshot on how data is used in modern farming. "You can taste the algorithms" Listen at the link below
Curriculum Tags: MDM4U
http://fivethirtyeight.com/features/can-you-taste-the-algorithm-in-this-arugula/

I made a quick post on a fun data set for making bar or circle graphs about the types of new Star Wars toys. I think this is a good set to help show why bar graphs are better than circle graphs.
Curriculum Tags: Gr7, Gr8, MDM4U
http://found-data.blogspot.ca/2016/01/where-are-rey-star-wars-toys.html

It is EQAO season and that means that teachers are looking for different ways to have their students practice. A relatively new online service (mentioned here before) called @KnowledgeHook has a big advocate in @mathletepearce. In this recent post he points out their EQAO practice online quiz gameshow. Something worth a look if you are looking for more interactive ways to practice for EQAO.
Curriculum Tags: MPM1D, MFM1P
https://tapintoteenminds.com/9-eqao-math-gameshow-practice/

I have asked myself this question many times. Why on earth are TI-84 graphing calculators so expensive. Read on to find out a possible reason.
Curriculum Tags: All
http://mic.com/articles/125829/your-old-texas-instruments-graphing-calculator-still-costs-a-fortune-heres-why#.YjLq4SBVe

I really like this "Day in the Life" of a teacher of math students with learning disabilities from @crstn85. We all know that teaching is a busy job but trying to accommodate students with LDs makes things that much tougher.
Curriculum Tags: All
http://drawingonmath.blogspot.ca/2016/01/a-day-in-life-teaching-math-to-students.html

This reminded me of Calculus the Musical. Thanks to Michele Cooper for this one.
Curriculum Tags: MCV4U
http://www.teachertube.com/video/calculus-rhapsody-178211

It's always good to be made aware of examples of misleading statistics. And I particularly love those that show this particular paradox with taking averages and percents. And because this is a TED-Ed video it is nice and short and has support material with it.
Curriculum Tags: MDM4U

I have long said that kickers have become integral parts of professional football teams. It seems the data backs that up. In particular I love the idea of sending kickers from today back in time to play to see how effective they could be. This graph shows it but check the link out for more evidence to convince your football loving friends.
Curriculum Tags: MDM4U
https://fivethirtyeight.com/features/kickers-are-forever/

Do you have kids that are into popular music? Then this post from @fivethirtyeight might be for them. It compares Nicki Minaj and Drake. More specifically how including them as a guest on your song might help that song's popularity. That is, which is bigger, the Drake Effect or the Nicki Effect. Spoiler alert, they conclude having Nicki on your track is better. But there is a lot of data here to help compare the two situations so if you are looking for kids to do some inferencing on graphs then this post might be an interesting way to do it. Caution, however, not surprisingly both of them have played on songs with expletives in their titles. Some are mentioned in this post. Because of that you might want to limit this to older students.
Curriculum Tags: MDM4U
http://fivethirtyeight.com/features/drake-effect-nick-minaj/

## Friday, January 8, 2016

### Math Links for Week Ending Jan. 8th, 2016

I love the way this blog post starts out:
"Last night I decided that it would be useful for my students to have more practice with the graphs of combined functions"
And then @marybourassa creates a Desmos Activity about combining functions, posts it on Twitter for feedback then shares it out. We are truly living in a great time. If this was 10 years ago, that would be just another worksheet. Now it's an interactive activity that has been vetted by teachers from across North America. Seriously, it's a good time to be a math teacher
Curriculum Tags: MHF4U
http://marybourassa.blogspot.ca/2016/01/combined-functions-desmos-activity.html

We have been posting a few "Tower Challenges" on our Engaging Math Blog. They are all review assignments where students answer questions to accumulate building materials to create the tallest tower in the end. Here is one for grade 8 on Algebra and Equations.
Curriculum Tags: Gr8
http://engaging-math.blogspot.ca/2015/05/gr-8-algebra-and-equationstower.html

I have created a new post on my Found Data blog. Here I blog about data sets that can be used to teach statistics. On this latest post the data is real-time info about earthquakes and is good for any single variable analysis.
Curriculum Tags: MBF3C, MDM4U
http://found-data.blogspot.ca/2016/01/earthquake-database.html

I always love calculus activities and although this is not an "activity" per se, I love the simplicity of the beginning with this rate of change worksheet. Download at the link below and as the commenter suggested, also try out the @Desmos activity Waterline.
Curriculum Tags: MCV4U
http://mathteachermambo.blogspot.ca/2016/01/happy-new-year-2016.html

I thought this was a nice little review for what the solution for a system of equations was from @DaneEhlert. Good use of the football video we have (hopefully) all seen.
Curriculum Tags: MPM2D, MFM2P
http://whenmathhappens.com/2015/12/01/systems-of-equations-re-engage/

I really like this new video from @numberphile on the iPhone of the sliderule. I honestly never really considered how they work but you could easily incorporate them in your classes when dealing with estimation.
Curriculum Tags: All

Here is a cool animation for when you are talking about tessellations.
Curriculum Tags: Gr7, Gr8
http://geometrymatters.tumblr.com/post/136807764669

More tiling can be found here with this competition. Check them all out at the link below. Thanks to @MathMunch for this one
Curriculum Tags: Gr7, Gr8
http://spidron.hu/scientile/submissions.html

Dang, I missed Right Triangle Day! Dec 9, 2015 (12/9/15). I wonder when the next right triangle day will be?
Curriculum Tags: Gr8, MPM1D, MFM1P
http://mrhonner.com/archives/15406

I love creative discounts. And I love @MrHonner's discussion on how to maximize the savings. Check out the link for that.
Curriculum Tags: Gr7, Gr8
http://mrhonner.com/archives/15628

## Saturday, January 2, 2016

### Math Links for Week Ending Jan. 1st, 2016

Because this is the first post of the new year, I thought it would be appropriate to have a New Year's based link. Some linear data here to measure the speed of a cork as it leaves a champagne bottle. It could be used to talk about rates of change or linear relations. And as an extra bonus you get the data on the streamers from a popper and both data sets can be edited (if you create an account on Plot.ly) and they are interactive (mouse over the graph below)
Curriculum Tags: MPM1D, MFM1P
http://www.wired.com/2015/12/the-physics-behind-popping-champagne-bottles/

More great stuff from @Desmos. There new set of activities called Marbleslides. This is a gamified version of the match my line type activity. The game part is that you have to use knowledge of function transformations to "collect stars" from falling marbles. They have one for linear functions, one for parabolic functions and one for sinusoidal functions (using radians). Some of them are challenging but I think most kids would be engaged in using them.
Curriculum Tags: MPM1D, MFM2P, MPM2D, MCR3U, MCF3M, MBF3C, MHF4U
https://teacher.desmos.com/marbleslides-lines
https://teacher.desmos.com/marbleslides-parabolas
https://teacher.desmos.com/marbleslides-periodics

I am really liking all of these examples of systems of linear equations that are the result of real situations where the answer can be revealed by making a measurement or a physical count. I think that makes it much more tangible for students. Here @mathletepearce has a few different examples dealing with the weights of various objects but when given only the total weight of groups of items. So you can create the linear equations and then reveal the answer. Watch all the videos for the three examples here.
Curriculum Tags: MPM2D, MFM2P
https://tapintoteenminds.com/3act-math/piling-up-systems/

Can you tell the difference between math and poetry? Take this online quiz and find out if you can. Personally I got 9/20 which I contend means I don't see the difference between the two.
Curriculum Tags: All
http://blogs.scientificamerican.com/roots-of-unity/mathematics-or-poetry-take-the-quiz/

This is a really short post (short enough that I can put the whole thing here) from the Better Questions blog, but here are three questions you can add to your repertoire:
• Why does that work?
• Can your idea be represented in a different way?
• Why does the answer make sense?

Don't forget to follow the Better Questions blog. Thanks to @misscalcul8 for this one
Curriculum Tags: All

There are too many videos to link here but if you go to this Math in the Movies site you will find so many clips from movies that have connections to mathematics. From area of a circle (in Castaway) to to the Fibonacci sequence (in The DaVinci Code). Browse away and find something you can relate to your math classes.
Curriculum Tags: All
http://www.math.harvard.edu/~knill/mathmovies/

Some fun stuff from @benorlin. Report cards for famous mathematicians and physicists. Click on the link to see them all
Curriculum Tags: All