## Friday, October 17, 2014

### Math Links for Week Ending Oct. 17th, 2014

We have been adding to our Engaging Math blog and we have a few new ones this week. The first is a Tarsia puzzle for relating squares and square roots that we made. The premise is that you have a bunch of questions and matching answers. Students have cards that have either an answer or question on the edge. They then have to match up the edges that have the pairs of questions and answers and eventually it will make a shape. These are really good short activities that you can pull out at any time. We have several of these and there is a link for making your own on the Mr. Barton Maths site.
Curriculum Tags: Gr7, Gr8
http://engaging-math.blogspot.ca/2014/10/tarsia-puzzle-squares-and-square-roots.html

Awesome post at Slam Dunk Math. In this one they use snap cubes to model factoring of expressions like y=x3+4x2+5x+2 by physically creating a rectangular prism from the cubes. It is also really great for students in courses like MHF4U to actually use some manipulatives to help solidify mathematical understanding. They need it to. The one issue with this activity that I see is that you need a huge pile of cubes. Despite that I could see doing this for any class where factoring a polynomial is needed (that's why even though this particular activity was done for MHF4U, I tagged the other courses as well). So I would actually do it in grade 10 with quadratics just to get that ball rolling. Seriously, check this activity out.
Curriculum Tags: MPM2P, MFM2D, MCR3U, MCF3M, MBF3C, MAP4C, MHF4U
http://slamdunkmath.blogspot.ca/2014/10/volume-length-width-height.html

I like matching activities and I also like doing those types of activities in courses that traditionally you wouldn't do that in. In MCR3U and MHF4U we have to prove trig identities and it is tough sometimes to shake that up a bit. So with that said I like this activity where students are given a sheet of cards and have to build the identities from them. The instructions are that they are just to start by finding cards that are one step from each other and eventually get to a full set of steps. Now I don't know if you could take this set and use them directly in either class (due to the constraints of the expectations) but you could easily make your own set. As seen here, it was just hand written so this would take very little time. Either way you can download this set here.
Curriculum Tags: MCR3U, MHF4U
http://mathteachermambo.blogspot.ca/2014/10/trig-identity-match-up-activity.html

This is a surprisingly fun activity that takes the mundane activity of multiplying integers and makes it into a game. All you need are decks of cards (red cards negative). Students are in groups of 3. Two students choose a card without looking at them and put them face out on their foreheads. The third person multiplies them together and gives the answer. The card holders (mind readers) now try to guess what the original cards are.
Curriculum Tags: Gr8, MPM1D, MFM1P

I have always loved the Geometer's Sketchpad balance model sketches. They have tweaked them over the years and they have become really good. On their Dynamic Number website they have several, including this one that uses symbols and the balance method to determine unknowns (without the use of variables). You can try it out on this blog post without the sketchpad software and I strongly suggest that you do
Curriculum Tags: Gr8, MPM1D, MFM1P
http://blog.keycurriculum.com/a-balance-model-approach-to-algebraic-equations/

As I have been saying, Kyle at the Tap Into Teen Minds blog has been busy. I think he has found more hours in the day or something. Check out this 3Act Task based on the big nickel in Sudbury. What's the premiss? How many actual nickels would it take to make the big nickel? (and all the derivative questions). Good for proportional reasoning and volume of right prisms.
Curriculum Tags: Gr7, MPM1D, MFM1P, MPM2D, MFM2P, MBF3C, MCF3M
http://tapintoteenminds.com/3act-math/big-nickel/

Another 3Act task from Tap Into Teen Minds is about investigating the relationship between volume of a pyramid and right prisms of the same base (spoiler alert: one is a third of the other). This is an investigation all should do, especially if you have the plastic prisms for the demonstration (and especially since it is part of the grade 9 curriculum). But if you don't you can just show the videos Kyle has made (see the one of the 3rd acts below but look at them all on his blog post).
Curriculum Tags: MPM1D, MFM1P

Some great videos here from the Science Museum on Math. Including a few that are interviews with the writers of the Simpsons and Furturama. I like the one where they talk about Fermat's Last theorem but click on the link to see them all.
Curriculum Tags: All

And here is a longer form talk by Simon Singh about his book, Simpsons and their Mathematical Secrets.
Curriculum Tags: All

Because, why not?
Curriculum Tags: All

I saw this cloud the other day on the way home and thought it was parabolic. I used Desmos to check it out (see link below) and it looks like it is close but not quite.
Curriculum Tags: MPM2D, MFM2P, MBF3C, MCR3U, MCF3M
https://www.desmos.com/calculator/5n3oh2dgtm

When you see #WCYDWT on the Twitter then you are seeing a Dan Meyerism that stands for What Can You Do With This? Its a picture or a video that might allow for some math. Here is one from Mathy Cathy. I think you could do some proportional reasoning or maybe some measurement and possibly some Pythagorean theorem using this image as a base.
Curriculum Tags: Gr7, Gr8, MPM1D, MFM1P
http://www.mathycathy.com/blog/2014/09/iphones-wcydwt/

I like visualizations of things and here is a nice visualization of the difference between 0.3 and 0.33
Curriculum Tags: Gr7, Gr8
http://mathfour.com/numeracy/difference-between-point-3-and-point-33-visually