Fun ideas for teaching maths in the classroom

Let’s face it most people do not enjoy mathematics. Often students have told me that they find the subject boring or they felt lost from the very beginning.

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Graphs - Use your Calculator

Graphs are an important section in maths and one of the most common questions in an exam is how to draw a graph. If you need help with this section then read this article.

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Help!! I don’t get it!!

So you're sitting in the exam staring at the maths question in front of you and thinking: “help!! I don’t get!! – What am I supposed to do here? ” Well here are some tips for you:

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National AMESA 2013

The 2013 AMESA conference was held in Cape Town this year. The weather attempted to play ball and there were lots of exciting things that happened at the conference. 

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Why should you choose Maths?

Maths and science are found in many aspects of any career – from basic budgeting to the development of drugs to fight cancer or HIV/Aids.

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Real Life Analytical Geometry

We use analytical geometry in a number of applications – from engineering to designing aeroplanes to flying aeroplanes to designing the house that you live in.

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AMESA Congress

Michelle and I attended the AMESA (the Association of Mathematics Educators in South Africa) from the 24th to the 28th of June 2012.

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Enter This Weeks Competition

 

Volume

Which has the greater volume: A cylindrical can with diameter, 2d and height, h, or a rectangular can with length, d, breadth, d and height, 

 

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How to....

prove the CAST diagram

On your SHARP EL535 calculator press . Then type in   .

For X_Start: type in  90 and 

For X_Step: type in 15 and 

Look at the answers between -90 and 0 - are they all positive or all negative? 

They are all negative: therefore sin is negative between -90 and 0.

Between 0 and 90 sin is positive,

between 90 and 180 sin is ? 

between 180 and 270 sin is ?

and between 270 and 360 sin is? 

Press  twice then type in  . Leave your X_Start and X_Step as they were for sin, so press  twice. Again look at the ANS column and say between -90 and 0 whether cos is positive or negative; for 0 to 90, 90 to 180, 180 to 270 and 270 to360. 

Repeat the process for tan. 

Now write down all your information in a table:

  sin cos tan

who is

positive?

quadrant
-90 - 0 - + - cos 4
0 - 90 + + + all 1
90 - 180 + - - sin 2
180 - 270 - - + tan 3
270 - 360 - + - cos 4

 

Now we can summarise our results in a the form of a cartesian plane, where each quadrant represent the positive function:

And that is where the the CAST diagram comes from. The line between C and A represents 0 or 360, the line between A and S represents 90, the line between S and T represents 180 and the line between T and C represents 270 or -90.