Monthly Archives: March 2013

46. Pursuit Curve from the past

This project hit all the buttons for me (Maths, Craft, Art, fair bit of Black).
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The pattern is in the Knitty archive – OpArt. I made my version for the first-born child of friends.

Longer ago than I care to remember I collaborated on a instructional for pursuit curves on PrimaryResources.co.uk.

Although they aren’t a key part of the Maths curriculum, pursuit curves shouldn’t be overlooked or dismissed as an end of term activity. To produce an accurate picture, pupils need to carefully use measuring and drawing equipment – this makes it a good way to start a measures topic.

45. Show me the money

If you offer personal finance as a compulsory part of the curriculum, stop reading now.

‘Pay day loan’ companies have been the subject of several news stories over the last few months. Do they make money from those suffering from financial strife? Are the people who take them out too short-sighted to see the long term impact? Are they bad at Maths?

Personally, I don’t think there is a simple answer to any of it. That is the reason I’ve started including pay day loans when I do percentages with KS4 pupils.

Loan calculator
This idea arose when I was revising with older pupils who had the skills to work out percentages, but were struggling to apply them.

I showed them the loan calculator sliders on Wonga.

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I asked the class to estimate how much different loans would cost for different numbers of days. They showed their answers on whiteboards. I then showed the actual amount owed and we discussed it.

The questions they came up with and how they justified their choices were brilliant.

Student Examples
If you are always £100 short at the end of the month and continually paid off the loan with interest, what would you owe after a year?
(They spotted that after each month you would need £100, plus an extra months interest etc)
What is the APR? What does APR mean?
(It was 4214% on the day we discussed it)
Why do you pay fees on a loan?
Are pay day loans a bad thing as a one off, emergency solution?
(They were split on their answer to this one)

Some of these questions wouldn’t be relevant in a GCSE, but they are life skills which will hopefully benefit them in the future.

By the way, they were ‘gobsmacked’ when they realised how much interest you pay back on a mortgage and what percentage of your wages go on monthly repayments!

44. Bad Science

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The application of statistical evidence in clinical trials is the underlying theme of Ben Goldacre’s work on his Bad Science website.

Bad Science

It is full of examples of where evidence, statistics and common sense are ignored in favour of good PR and dodgy scientific claims.

The book ‘Bad Science’ is an enthralling read. I had the audio book on my ipod when I was in hospital a while ago and still had to get the paperback because I wanted to reference and reread sections. Thanks to PG for originally telling me about it.

43. Visualising percentages

Percentages are all to do with proportion, but this seems to escape the understanding of some. If you calculate 20% of £15, this is different to 20% of £25. The 20% is not a fixed quantity. How can you explain this to visual learners?

Visual Percentages/Proportion

Equipment
Pencil
Ruler
Paper – squared makes the task easier
Coloured pencils (optional)

Calculations
Find 20% of 15, 10 and 0.

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Construction
Draw a 15cm line, mark 3cm along it.
Move down 5cm.
Draw a line, mark 2cm along it.

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Join the ends of the lines with a ruler and indicate this with a cross.
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This should be 10cm lower than the bottom line.
Repeat, joining the 3cm and 2cm points.
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Shade in the smaller triangle.
Label the lines.
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The Maths bit
The width of the triangle indicates the whole amount (100%).
The shaded width represents 20%.
The unshaded width represents 80% (Ask students if they know why).

The whole diagram represents 20% of any number from 0 to 15.
This can be adapted for any number and percent. It visually shows that as a number gets bigger the percent increases proportionally.

You can also use this to investigate fractions.

Note: This is for comparing widths. You can challenge your students to prove whether it is also true for the areas of the triangles.

42. Fake texting, Real learning

I discovered this great website, ifaketext which generates roughly six lines of fake text messages.

Ice-breaker

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I used it as an ice-breaker for revising cumulative frequency. The class read the texts and discussed what they could remember and whether those pointers were helpful. There were four screens of hints.

In fact the class liked it so much I printed out the fake screens and they stuck them in their books.

Motivation
I’m also using the site to encourage more engagement with homework for lower ability students.

I could have set the homework task ‘Write down key facts that help you work out percentages’. Instead I asked them to ‘Imagine a friend had texted for help with a percentages homework. What would you text back?’

When they hand their work in, we can turn the best advice into fake texts to stick in their books or use in a wall display.

Two of those who have homework ‘issues’ have already said they are going to text each other tonight to do their work. This resulted in the following unusual question:
‘Please Miss, can we hand in our work by showing you our phones?!’

41. Revision traffic lights

Visual revision aid today!

I asked my GCSE students to ‘traffic light’ all the learning objectives from the course. The categories were:
Red – I really need help with this.
Amber – I’m okay with this, but I will need to revise before trying exam questions.
Green – I’m fine to try GCSE questions on this.

They worked together to write up their top responses on coloured paper. There are two of each colour so they didn’t get too crammed.

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Now I know where they need help/ a confidence boost and the class can see their concerns addressed as we work through their lists. Of course, I’ll add in topics they missed.

This activity gives them a sense of ownership of their learning.