Making numbers meaningful in geography

My first geography blog and I have decided to focus on my weakness - numbers.  I am going to blame my dad who professes he is no good with numbers, perhaps why he isn't totally sure my age.  I have probably mirrored his behaviour for many years, declaring I was 'no good at maths' despite picking up a reasonable grade in GCSE maths.  This was until I came across Gapminder, I challenge anyone who says they are not interested in numbers not to enjoy the data they produce.

For a number of years I have been trying to work out how to remember key data better so that I can help numerically challenged students.  I tried to make numbers into pictures producing a lovely visual image for the 2004 tsunami - a swan (number 2), two doughnuts (0) and a boat (4).  Although this has helped me to remember the date, it is only of limited use for key data for all case studies.

It was a student who set off the lightbulb moment when studying Bangladesh as an example of coastal flooding.  On a discussion of accretion, we noted down the figure 1.2 billion tonnes per year, the amount of silt transported by Bangladeshi rivers annually to the sea.  A mathematically savvy student said 'Wow that's 4 million jumbo jets'.  This really put the statistic into context, we could picture 4 million jumbo jets and so could imagine the weight of this silt.    Thanks to this student we gained a greater understanding and a much more memorable number.

In my next lesson with year 13 we were studying The Grand Renaissance Dam and looking at 6,000 megawatts of electricity being provided for Ethiopia. It occurred to me that I should find out what 1 megawatt could provide.  When we worked out 1 megawatt provides enough for 650 UK homes it helped us to evaluate the strength of this evidence in terms of how this could help Ethiopia to develop. 

When we look at the cost of top down infrastructure schemes we will compare it to other schemes and consider who benefits from these costs.  When you compare HS2 (£98 billion), China's North-South Water Transfer project (£62 billion) and The Grand Renaissance dam (£3.6 billion), the Ethiopian scheme appears to be quite the bargain (although local costs/labour and regulations all affect costs).

I always encourage my students to learn 3/4 key facts per case study, now I will encourage them to cast a critical eye over the data in front of them.  For example when studying a regeneration scheme that produces 400 jobs, we will ask questions about that data.  What percentage would this be of all jobs in the local area?  What types of jobs will this produce?  Are they jobs local people are qualified to do?

So my mission from now on is to interrogate the data in my case studies, to make meaningful calculations and connections so that the information sticks.  I will let you know how we get on.

Since the first blog I ventured further into costs:

So on looking at the water management project in China, I noticed that the cost fluctuates depending on what source you get your information from (between $62bn and $100bn) so this was a good teaching moment.  The costs are estimated by the government so we looked at how a government might downplay the costs of a project (particularly as data from the Chinese government may not be reliable).   

Also it occured to me the word billion is banded about very much and it brought to mind the £22 billion pound contract for SERCO for track and trace.  So I got to investigate how much is a billion (I remember from school some vague difference between the US and UK).  This article sums it up and is a useful video to show students.

how much is a billion?