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'Bracelets' printed from http://nrich.maths.org/
Why do this
problem?
This
activity is good for engaging pupils in number patterns,
symmetry, factors, multiples, algebra and shape work, and allows
them to be creative. It should also encourage pupils to persevere
for a longer period of time than perhaps is usual.
Possible approach
This is best introduced by physically looking at bracelets
made of beads and asking the pupils to talk about what they
notice.
Beware that when children are counting or communicating
generally about what they've done there is a tendency to count the
number on each side of a shape inaccurately. In this example:
... there is the confusion of counting $4$ on each side and
then multiplying by $6$, instead of counting the "new ones" each
time and saying that there are $3$ new ones on each side.
Having dotty square and triangular paper available may help
the children. Just let them enjoy this and see what
opportunities arise!
Key questions
Tell me about the shapes you've made.
How many beads would you need for the next size up/down?
Possible extension
Simply asking the question "I wonder what would happen if we
...?" will encourage learners to take the activity in new
directions.
Possible support
Any practical resources will help the majority of pupils,
although some may like to construct them on a computer while others
may prefer to draw their bracelets. I found old fashioned curtain
rings to be really good but I guess that coins would also be
useful!