Sunday, 28 February 2016

Geometer's Sketchpad - Trig Ratio Generator

When using the Geometer's Sketchpad (for both computer and iPad) it is often better to "start from sketch, not from scratch". That is, give students a premade sketch rather having them build something from nothing (as many textbooks would have you do).
In this activity, students can practice two very specific skills dealing with trigonometry. The first is simply being able to correctly place the names of the sides of a right triangle (opposite, adjacent and hypotenuse). Students drag the side names and then can check their answers and then randomly generate another triangle to try again. The second is one where a random triangle is generated that shows information about two sides and one angle. Students then drag parts of an equation to create a trig ratio equation. They can check their answer and then randomly generate other right angled triangle to try again. 
This is not meant to be something that a student uses for a long length of time but instead just some quick practice to re enforce the basic ideas from trig ratios.
  • MFM2P, MPM2D - determine, through investigation (e.g., using dynamic geometry software, concrete materials), the relationship between the ratio of two sides in a right triangle and the ratio of the two corresponding sides in a similar right triangle, and define the sine, cosine, and tangent ratios.
  • MCR3U, MCF3M, MBF3C - As review
  • All that is needed is the electronic download (below)
  • Note that this really works well on an iPad using the Sketchpad Explorer App (which is free)
  • You can also use this on any web based computer (or Chromebook) with this Web sketch
Watch the video below to see how to use the sketch

Did you use this activity? Do you have a way to make it better? If so tell us in the comment section. Thanks

Friday, 19 February 2016

Number Sentences Sort (update)

One of the smaller expectations we have to deal with is the ability for students to interpret algebraic equations. You know: "what does 2x + 1 mean"?. We created this very simple sorting activity where students are given expressions (and equations) and the sentence to describe them and have to match them up. This is meant to be an activity that is relatively quick. We have two versions here. One for grade 7 that only has expressions and one for grade 8 that has equations as well. We also have an Explain Everything version of each so that if you have an iPad (or Chromebook), with that app, you can have your students sort them electronically. This can also be used as review in Grade 9.
Note: This is an update to the same activity posted last year but now with a grade 8 and Explain Everything version
Double Note: This has been updated again to now include a Desmos card sort. So both card sorts are now transferred to this new Desmos feature. You can learn about Desmos Card Sorts by clicking here. Download the Teacher versions (which you can copy) of these activities below in the download section.
  • Gr7PA - translate phrases describing simple mathematical relationships into algebraic expressions using concrete materials
  • Gr8PA - translate statements describing mathematical relationships into algebraic expressions and equations
  • MPM1D, MFM1P - As review
  • For the grade 7 version there are four different (but similar) sets. One set per page. For the grade 8 version there are three different (but similar) sets. One set per page. 
  • Print each page on card stock (we also suggest laminating). We suggest that each set be printed on different colour card stock for easy sorting. Cut each out and put each set in an envelope.
  • Obviously you will have to decide how many sets you will need for your class depending on whether you pair students up or not. 
  • Note that in the version with equations, there are some algebraic expressions that do not have matching sentences. In these cases, students will have to write their own.
  • If you choose to use the Explain Everything version, then you probably want to download that .xpl file and put it on a server where your students can get easy access to it. 
Explain Everything Screenshot
  1. Depending on how many students you have you may want to do this individually, in pairs or in larger groups. The activity is not super complex so we don't recommend anything bigger than pairs. 
  2. Students take each set and sort the algebraic expression with the written version. 
  3. When they are done their set they can trade with another group that has a different colour of cards. If they are using the Explain Everything version then they can just go to the next slide. 
  4. There is a homework sheet for consolidation that includes both expressions and equations as well.
Did you use this activity? Do you have a way to make it better? If so tell us in the comment section. Thanks