Thursday 16 May 2013

Numeracy stops here

History and Maths

If you have ever read the book ' What is History?' by E. H. Carr you may have come across the idea that 'History stops here.' What this mans is that some historians in the past believed that the History that they wrote was the definitive view; there was no other interpretation. Of course History is constantly being rewritten in the light of current ideas, attitudes and data.

The way I was taught is the only way, 'numeracy stops here'. This is the view of many parents and teachers. They believe how they learnt to add, subtract, multiply and divide is the only correct method to use, anything else is ‘strange’, not ‘proper’ or at worst some kind of  trick being played upon their child. None of this is true of course. Each child has his or her own way of learning and remembering things and once confidence is gained using their own method they should continue using it.

 Subtraction


Jim, like many pupils could happily subtract when the sum which looks like this.


However as soon as we introduce something more complicated anxiety sets in, he had convinced himself that he couldn’t and never would be able to remember how to in his own words ‘do it when the number on top was smaller’. Such as in the example below. We have all been there as teachers or parents with our pupils or children wanting to subtract 7 from 3 because they can’t remember or don’t know why they have to do in effect 13 minus 7.


A succession of teachers had tried and failed to teach Jim how to do subtract using the traditional method and failed, his parents despaired also having failed to teach Jim how to subtract. He was now 16. Jim is a bright lad, a visual learner, he wanted to subtract so that he could pass his exams.
 

Open number line


Jim was very comfortable with the open number line, so I decided to show him how to use it to subtract. First I drew the line like the one below and explained that we were at going to go from 17 to 43. I marked on the two numbers.

 

 
 
Now I asked Jim to jump to the nearest 10 from 17, he happily drew a line from 17 to 20.

 

How about jumping to the nearest 10 to 43 I asked. ‘What 40?’ he queried. He then drew the next jump and without prompting he then drew the final leap.

 


So how far have you jumped I asked him to which he replied 26. It was then only a small step to make the connection between this method and the subtraction su  set out in the traditional way. Jim was thrilled at being able to do subtraction with, as he termed it, ‘difficult take aways’. He successfully continued to use this method with ease and success, passed his exams and reduced his fear and anxiety when tackiling Maths.

 

Many of you may dismiss using this method as not being correct but it worked for Jim. It may not work for everyone but he was successful and solved problems so who is to deny him, or anyone that but adherence to other methods just because that was how they were taught.

 

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Wednesday 15 May 2013

Choose three numbers and ...


Ever felt that sinking feeling as you are about to tackle fractions again? You can imagine what the pupils think, well you probably knoe when they say ‘We’ve done this.’ Or ‘Not again’. Here is an idea tht will give a different slant to the fearsome task of teaching factions.

 

Step 1

Ask for 3 numbers between 2 and 9 inclusive. Write them on the board. Now ask the pupils in pairs to make as many different fractions as they can in 2/3 minutes. At the end of the allotted time collect the results on the board, the chances are they’ve forgotten to repeat the numbers with same numerator as denominator. Add any they have missed.

 

Step 2

Again in pairs or groups ask them to put the fractions into groups that appear the same. Collect the results, hopefully you will get top heavy fractions, equivalent fractions and ‘normal’ fractions. Ask them how they could be displayed in a table. Again some paired or group work.

 

Step 3

Now demonstrate that probably the most effective way of showing the results is in a table like that below. So for example if the numbers chosen were 2, 3 and 7 the table would look like this.

 

 

Step 3

You can now start to ask questions such as what is special about the diagonal with the entries 2/2, 3/3, 7/7? What do they equal? What other numbers can equal these?

 

What is different about 3/2, 7/2, 7/3? What are these type of fractions called? Hw can we change them?

 

I am sure you get the idea, the variations are endless and where you go depends on the class, their prior learning and what you want to achieve. This can also be extended to 4 numbers or where ever you want.

 

This idea was taken from the book ‘Starting points’ by Banwell, Saunders and Tahta published in 1972. A vision of how maths education could have gone. It would be interesting to compare it to today’s practice in classrooms throughout the world.

If anyone has used the ideas that I have given you over these last few blogs how did it go? Were they successful? How did you improve them? (I'm sure you can). Please leave a comment.

Tuesday 14 May 2013

Adding fractions - again and again and again ...


For years I taught adding fractions the traditional way. I taught it to the same pupils aged 11, I then taught it to them again aged 12. Yes you’ve guessed it 13, 14 , 15 and 16. Colleagues I worked with did the same, all with the same degree of success, or should I say failure, what is wrong with these kids we would say they just don’t get it. After a long, long time the ‘penny dropped’, it wasn’t them that didn’t get it, it was us Maths teachers.

 

Last night I taught a 15 year old to add fraction together in 15 minutes. She said ‘Is that it, it’s easy, for four years I was so confused and now … wow.’ I then had to teach her mum to add two fractions together who said why doesn’t everyone do that.

 

Most students can add two fractions together if the denominator is the same, this fact is easy to establish. You then need to tell them this is the only way to add two fractions if the bottom number is the same. Hopefully they agree. You then present them with two fractions like those below.
 

Now highlight one of the denominators and say you will use this to add the fractions. I find it really helpful to use colour, don’t dismiss this simple trick if you want to be successful and more importantly if you want the pupils to be successful.

Now say you are going to multiply the other fraction by the highlighted 4. Like this
 


Now highlight the other fraction.



Follow the same process. Multiply the other fraction by 3.


Finally complete the calculations like this


Point out the denominators are the same and then complete the sum.

 


After a couple of examples the pupils will happily be adding fractions. OK I know it isn’t perfect, such as when you have denominators of 2 and 4 but if you want them to be confident with adding fractions it is a really brilliant method. You have to tech pupils to cancel down so the problem of denominators of 2 and 4 is eventually tackled.

Monday 13 May 2013

Stand up/Sit down - times tables practice


Times tables - how can they stand it?


Have you ever struggled to find another way to teach multiplication or times tables? I have. It is never easy to find new ways to teach and/or practice multiplication tables. The kids are probably under pressure from home to learn them and in turn it increases the pressure on you, the teacher. Governments also use them as a handy measure of progress that the general public understand.

A fun activity

 This is great fun and can produce lots of laughter in the classroom. It is particularly  useful when the class is a bit sleepy, such as after lunch. (Or even when you are feeling a bit low on energy.) Equipment needed, NONE!

  • Tell the class they have to stand. You are going to call out numbers in the three times table (for example). If the number is in the three times table they have to stay standing BUT if its not they have to sit.
  • You say the number 9 staring intently at the class. No movement. 3, the same. 10 and the class sits down, or at least a few confident souls do and the rest follow. Once they have the idea you can continue, with the calling out of numbers becoming incresingly rapid. You can of course fool some by a slight bend of your knees as if you are about to sit down, even when you call out  number which is not a multiple of 3. Who follows your lead? Someone will. Continue until you think they, or you, have had enough.

  • This is fun and it enables you to see who is secure in their knowledge of the 3 times table, or whatever table you chose; it is an almost instant assessment tool.

Variations

  • Of course you can use other multiplication tables, but sticking to our three times table you could start to use 2 X 3, 4 X 3, 6 X 5, 2 X 7, etc. see if they can work out which are in the chosen multiplication table.

Order of teaching

I think there is a distinct order in which times tables should be taught, namely 10, 5, 2, 4, 9, 6, 3, 8 and 7. Experience has shown that these are the most difficult in ascending order.

This excellent book by Steve Chinn, 'What to do if you can't learn your multiplication tables', discusses the problems and strategies for learning the multiplication tables. He is an expert on learing difficulties, especially dyslexia and dyscalculia, who shares his knowledge through a series of books focused on Mathematics.
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Please feel free to leave a comment, I would really appreciate it.

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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