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
http://www.mathalicious.com/2013/09/prisn/



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
http://sketchexchange.keypress.com/sketch/view/823/percent-guesser

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
http://www.androidcentral.com/new-google-services-uses-more-battery-old-and-google-needs-fix-battery-screen-already


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
http://17goldenfish.com/2013/04/23/first-past-the-post-and-the-dreaded-disease-z/





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
http://mtsmc.blogspot.ca/2013/04/patio-math-toddler-edition.html






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
http://learnandteachstatistics.wordpress.com/2013/09/02/khan-academy-probability/


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
http://christopherdanielson.wordpress.com/2013/09/04/college-algebra-with-christopher/


Yummy Math has a nice activity that uses an infographic from visual.ly 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
http://www.yummymath.com/2013/how-much-caffeine/

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
http://www.edudemic.com/2013/08/four-tips-parents-encourage-math-skills-home/

I think this building was designed by Dr. Heinz Doofenshmirtz. An application of parabolic focussing.
Curriculum links: MFM2P, MPM2D, MCR3U, MCF3M, MBF3C
http://io9.com/new-skyscraper-unexpectedly-generates-a-solar-beam-that-1263670017

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
http://blogs.smithsonianmag.com/science/2013/09/the-suns-magnetic-field-is-about-to-reverse/