Sunday, 12 May 2013

An algebra starter - money in my pocket



Algebra starter - just for a change

b7837b04d7a4c2e975b65d8e13f83780Want to revise basic algebra with your class? Want a quick starter that doesn't involve equipment, not even a worksheet?  This is a starter activity for you.

Use of algebra

 This activity is fantastic for starting algebra or revising basic concepts. You need to have some coins in your pocket or purse, preferably of a low denomination. Tell the class, as you jangle the coins (that you have out of sight) that you have some money but you don’t know how much. Ask them what shall we call the amount? A variety of answers will be offered, many quiet amusing, such as ‘cash’ ‘wonga’, ‘dosh’ or whatever the current vogue word is for money. Once you have arrived at a consensus for the change that you have in your pocket guide them to some algebra by saying that you will use one of their chosen words but you'll only use the first letter. Establish that the unknown amount of money in your pocket is m for example if you are using the word money.

The generous Maths teacher

Now in a fit of generosity, well all Maths teachers are kind, caring warm and generous, give someone in the class 1p. Ask how much you have in your pocket now. Again the answers will be very revealing, as they struggle with algebra, their understanding of the concept of an unknown and how it is represented, eventually the discussion should led to m – 1. Retrieve your 1p and now ask them how much now do you have in your pocket? Hopefully they will get to m.

The generous Government

Next explain that the Government has awarded all teachers a bonus of 5p which has just magically arrived in your pocket. I did have m how much do I have now in my pocket? n will be a popular response, this really does demonstrate their misunderstanding and misconceptions about algebra. That is why this exercise is so important. In a short time you should get to m + 5. Now ask how much you have if you give away 3p reminding them that you now have m + 5. Again the responses will be very illuminating, highlighting understanding, or not as the case may be. Keep asking questions of this nature. It is often useful to record your answers on the board. Vary the questions depending upon the responses.

Further work

This oral question and answer session is very good for highlighting misconceptions or building understanding. Further question could be ‘I have m in my pocket what do you have in yours?’ If they say m you say ‘so if we put our money together what do we both have? Or if they say c what do we both have? If I lose 2p what do I have? After I have lost 2p I double my money what do we have now? The variations are endless.

For another esy starer why no see Stand up/Sit down.
 
I suggest that you repeat this exercise at regular intervals just to keep the class on the ball. we all know how knowledge slips way if it is not used.  Repeating this activity will give your class a head start when it comes to basic algebra.
 
An excellent book for mathematical starters is 101 red hot starters.
 
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