This is a small collection of articles put together to give you some general ideas for secondary classrooms.
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Angle measurement: an opportunity for equity
Suggestions for worthwhile mathematical activity on the subject of
angle measurement for all pupils.
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Stacks of maths!
In this article for teachers, Bernard gives an example of taking an
initial activity and getting questions going that lead to other
explorations.
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The history of negative numbers
This article -useful for teachers and learners - gives a short
account of the history of negative numbers.
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Proof: a brief historical survey
If you think that mathematical proof is really clearcut and
universal then you should read this article.
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Enriching networks, inspiring teachers
Here are examples of how two schools set about the task of ensuring
that problem solving was an integral part of their curriculum.
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2010: a year of investigations
This article for teachers suggests ideas for activities built around 10 and 2010.
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A random rambling rant
A random ramble for teachers through some resources that might add a little life to a statistics class.