Friday, September 27, 2013

Math Links for Week Ending Sept. 27th, 2013

I am not sure of exactly what applications this might have in the classroom and it does have some limitations but I think the interface is really smooth and nice.
Curriculum Tags: All

I was watching the show Tanked (they make custom aquariums) and they did this neat thing where they had to make a martini glass so they cut a flat piece of plastic and then placed it on a form and baked it so that the plastic bent around the form to make the cone. It was very impressive. I tried to find the video but couldn't. I did, however, find a real company that makes these cones and they had a page on how they make them (including an Excel spreadsheet)
Curriculum Tags: MPM1D, MFM2P

I think that the concept of functions might be one of those things that sometimes doesn't get the treatment that it should. Here is an interesting treatment that uses the analogy of using a vending machine. Take a look.
Curriculum Tags: MCF3M, MCR3U

Here is a nice progression from similar lines to similar shapes.
Curriculum Tags: Gr7, Gr8, MPM2D, MFM2P

As far as I am concerned, you can't have enough activities that show how improbable it is for someone to win the lottery. As it is with other Yummy Math activities, you have to be a member to get the solutions and an editable version of the activity. I particularly like the link to the app to simulate the powerball lottery.
Curriculum Tags: MDM4U

I like this update of an older Dan Meyer activity dealing with the relationship between ticket cost and distance travelled/time taken for flights. A nice scatterplot/line of best fit activity. The main part of the update that I like is the use of Google docs.
Curriculum Tags: MPM1D, MFM1P, MDM4U, MAP4C

Whenever I can introduce an algebraic concept by first using a numerical method I am happy. Apparently I am not the only one. Here is one dealing with the distributive property. Thanks to Dan Meyer for this one.
Curriculum Tags: MPM1D, MFM1P, MFM2P

I really like this nice collection of Number Sense videos. Nine videos in all. Take a look at one of them below and the rest of them here
Curriculum Tags: All

A nice little tidbit of data
Curriculum Tags: Gr7, Gr8, MBF3C, MDM4U

Need some data about TV watching. Maybe after you see your favourite show
Curriculum Tags: Gr7, Gr8, MBF3C, MDM4U

Friday, September 20, 2013

Math Links for Week Ending Sept 20th, 2013

I really like Adam spencer. Maybe it's because he has a Phd in math but chooses to be a morning radio DJ. Or maybe because he is really good at taking complex ideas and making them understandable by most humans (usually in a humorous way). Here is his TED talk on prime numbers. Another great offering is his Book of Numbers where he looks at all the mathematical properties (and oddities) of the first 100 numbers.
I am a big fan of having part of an assessment being done with technology. Having taught math for several years in a computer lab I would regularly have part of the test done on the computer. I like how Amy Gruen mixed the use of cards and iPads running Desmos to do just that. Specifically here when it comes to transformations but you could see that this could be adapted to just about any topic. 
Curriculum Tags: MBF3C, MCF3M, MCR3U, MCT4C, MAP4C, MHF4U

Real World math is a site that uses the power of Google Earth and Google Sketchup (both free apps) to bring math to the real world. With lessons that are as simple as estimation to as complex as intersection of planes in 3D (with volume, line graphs and more in between). One small caveat. As a teacher you have rights to the full lessons but you have to request a password first. So you fill out a small form and they email you one. Simple as that. Thanks to Paul Georges for this one
Curriculum Tags: All

I love this series who's limit is e. Shown very nicely here on Desmos. I especially like the fact that in the table of values you can see the series being built.
Curriculum Tags: MCR3U, MHF4U

Having good questioning skills is not something you are born with. It is an acquired skill. Fear not. Here is a blog post that will give you 26 ways you can switch up your questions. 

You can always count on Yummy Math for quality resources. Here are a few of their more recent ones. As always the handout is free but to get the editable version and solutions you need to be a member.

This one is about the amount of caffeine in various brands if coffee. 
Curriculum Tags: Gr7, Gr8, MDM4U

This next one deals with a good topic for students. Does it pay to go to school. It may start out as if its a data management prompt (which it could be) but you can see how this can turn into something more when you deal with the wage values over the span of decades (and perhaps include interest calculations)
Curriculum Tags: Gr7, Gr8, MCF3M, MCR3U, MBF3C, MDM4U

This last one combines slope and Pythagorean theorem when talking about slopes of mountain trails. Since it has slope, this could be used in grade 8 as an extension or be modified to focus mainly on Pythagorean Theorem.
Curriculum Tags: MPM1D, MFM1P, MFM2P,

I have some mixed feelings about this site but agree with it in principle. Nix the Trix is a site that tries to address the prevalence of using "tricks" to teach math concepts. Think "move the negative to the other side and change the sign". I know that I have been guilty of teaching these in the past but I think I am evolving. By teaching these tricks we gain time in the short term perhaps but students only make those gains in the short term as well. That is, if they don't have the conceptual reason a "trick" works then its just that, a trick, and not a mathematic concept. Just one more rule to memorize with no meaning. No wonder we have to re teach so much from year to year. That being said this site tries to address these ideas in the form of an evolving Google Doc. Take a look.
Curriculum Tags: All

I really love this first day activity. It uses the "What do you know/notice/wonder?" theme. First get them thinking about math in general, then your course, then at the end hit them with a few questions to show the skills they have. In the activity on this post he uses a picture of the ISS but on a similar activity he uses this picture of an underwater bridge. You can see the results of the activity here.
Curriculum Tags: All

Really quick one from Dan Meyer. Perfect as a Minds On when talking about transformations in grade 7 or 8. Of course there is no need to show students this video, just create your own and work the magic in your own classes.
Curriculum Tags: Gr7, Gr8

I like this as a way to introduce trig functions in MCR3U and MCF3M. Follow the link to see the full idea of the lessons. But watch the video to get a sense of how to introduce the concept.
Curriculum Tags: MCR3U, MCF3M

Here is a great discussion starter about outliers
Curriculum Tags: MDM4U

Friday, September 13, 2013

Math Links for Week Ending Sept. 13th, 2013

I am not sure how long this has been around but it seems to be a repository for all of the in house created sketches for GSP. Very inviting site and these sketches really exploit the power of Geometer's Sketchpad. There is stuff for all grade levels and even an indicator for those sketches that are iPad friendly.
Curriculum Tags: All

Despite the title of this TEDx talk (Why Math Instruction is Unnecessary) I like how John Bennett takes us on his journey of discovery that much of the math that we teach is basically just a construct of our curriculum and not really necessary for everyday life. But the real focus of his message is that problem solving and critical thinking are.
Curriculum Tags: All

Many have long said that mathematics was the way to a high paying job. Well now I guess we have the data to prove it. The US Census has always asked about income and level of schooling but in their most recent surveys they have also asked what people's majors were. The Planet Money people have a great podcast on the results (long and short versions below). And the survey says: Applied math (engineering, computer science etc) seems top the list. What's at the bottom? Psychology. A couple of things that resonated with me about this were a) that, in general, it didn't matter where you got your degree and b) it really had more to do with supply and demand. If you want the actual pdf of the full study click here.
Curriculum Tags: All
Long version
Short version

I am way behind on the I Speak Math blog posts but this one about how now there are more #mathchat had a Twitter chat about the math topic of the day. Now there are these more specific chats that go on. From middle school math all the way to calculus and statistics. Take a look here for your favourite topic.
specific "chats" about math on Twitter now. For a while every Monday and Friday (I think)
Curriculum Tags: All

Another great TED talk about visualizing data. Chris Jordan is an artist who creates social commentary art that is often more than it seems (when you look closely at it). For example an image of the Titanic made of 67000 images of mushroom clouds (equal to the number of metric tons of uranium/plutonium being stored temporarily around the US). Check out his website ( to be able to zoom into his works (there are a lot of them). Here is a perfect way to mix social justice and data management.
Curriculum Tags: MDM4U

"Would you rather...." is a blog that specializes in posing questions that asks the reader to make a choice of two similar situations and use math to justify that choice. There are a lot of different math topics that could be used here but it seems many fit into the Number Sense strand (I could be wrong here as I just skimmed the site). None the less these are great starting points for math conversations.
Curriculum Tags: Gr7, Gr8, MFM1P, MPM1D

These math "mysteries" are all really attainable for many students to understand (ie they can easily mechanically verify them) but they are some of the most famous unproven theorems. A neat way for students to see how proving something definitely can be very difficult. Included are the Goldbach Conjecture, Perfect Numbers and Mersenne Primes (plus people have suggested others)
Curriclum Tags: All

I like this App to visualize Factoring from NCTM's Illuminations. Too bad it doesn't work on an iPad but its a nice visualization
Curriculum Tags: Gr7, Gr8

Here is a great way to introduce FOIL in secondary and in elementary I like the suggestion made by @emergentmath "Here's your lesson plan tomorrow: Stop the video after 1:30 and ask "why does this work?""
Curriculum Tags: Gr7, Gr8, MPM1D, MFM2P

I don't think you will ever need to describe how a Venn diagram works if you just show this example. There are more on the main site ( though not all dealing with data.
Curriculum Tags: MDM4U

Redbull sponsored a contest to take the image of extreme thrill seekers in action. Some cool pix but this one fits quite well with modelling quadratics. Just import this into GSP or Geogebra and model the strobed snow boarder with a quadratic. Note that it may look kind of flattened out but that has to do with the fact that the snow boarder is rotating in flight. But it's the centre of mass that follows a parabolic arc.
Curriculum Tags: MPM2D, MFM2P, MBF3C, MCF3M, MCR3U

Friday, September 6, 2013

Math Links for Week Ending Sept. 6th, 2013

I really like this example from the Mathalicious blog (even though they make a spelling mistake in the title - though @mathtans suggests this is on purpose prisn = prison). I saw this graphic earlier in the week when the blogsophere was making fun of it but Mathalicious has found a way to make it relevant to the math classroom. It deals with the idea of false positives in large samples. I have always gravitated to these examples as they really accentuate the problems with any sort of testing where the results are based on a probability or percentage.
Curriculum Tags: MDM4U

I have been starting to create some simple Geometer's Sketchpad files that could be used as a Minds On or intro to lessons. This one is a simple sketch that allows students to visualize a guess of how big a percentage is. They can check their answer, get a hint and then reset the question so it randomly changes the situation. It was designed to use the iPad version of GSP, Sketch Explorer. Try it out
Curriculum Tags: Gr7, Gr8, MPM1D, MFM1P, MAT1L

Here is a nice application of percent that is very real world. Dealing with percents of percents when talking about resource use on an Android phone.
Curriculum Tags: Gr7, Gr8, MPM1D, MFM1P, MAT1L

I like this activity because its hands on and its about sampling. Specifically dealing with the idea of the effects of sample size. Thanks to Dan Meyer for this one.
Curriculum Tags: MDM4U

Here is a nice real world optimization problem that deals with perimeter, area and money. Basically, how much money would you save to try to build this playpen on your own. Thanks to Dan Meyer for this one too.
Curriculum Tags: Gr7, Gr8, MPM1D, MFM1P

I don't want to spread negativity but this blog post about a Khan Academy video seems right on. It kind of exemplifies how the Khan videos are not really stelar in terms of the teaching (in this case having out right mistakes). They serve a purpose but they shouldn't be your go to resource. But that is not really why I like this post. I liked it because it uses something I hadn't heard of before (or at least didn't know the name of before). Using a two-way table instead of a Venn diagram. I agree that this seems to be way more informative than the Venn diagram. Check it out.
Curriculum Tags: MDM4U

There has been a lot of blog posts about analyzing Double Stuffed Oreo's to see if they are actually double stuffed. Here is a tweak dealing with systems of equations.
Curriculum Tags: MPM2D, MFM2P

Yummy Math has a nice activity that uses an infographic from about the amount of caffeine in various coffees. As it is with all Yummy Math activities there is a worksheet but if you want the solutions and an editable version of the worksheet.
Curriculum Tags: Gr7, Gr8

I think that these four suggestions are good though more relevant as kids are younger. I certainly agree that speaking well of math is the first step. We have an uphill battle in the math arena since most people have an easy time dissing math and of course that filters down to kids and then we get them as students. But I like the suggestion to play games. Using dice, cards, and problems solving skills on a regular basis is going to help kids in math class. Check out the other tips here.
Curriculum Tags: All

I think this building was designed by Dr. Heinz Doofenshmirtz. An application of parabolic focussing.
Curriculum links: MFM2P, MPM2D, MCR3U, MCF3M, MBF3C

Here is a scientific and topical example of periodic phenomenon. The reversing of the Sun's magnetic field. Could possibly be modelled with a sinusoidal function with a period of 11 years. Thanks to Joe Goulet for this one.
Curriculum Tags: MCR3U