Fractions jigsaw

Teaching and Learning Resources p.1
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Fractions jigsaw
Assessment focuses
AF1, AF2, AF3
Context
This activity, available from the NRICH website (www.nrich.maths.org/5467), was
about equivalent fractions.
The teacher gave the pupils a set of square cards that had each been divided
(diagonally) into four areas, with fraction expressions written on two, three or four
areas of each card. The aim was for pupils to find an arrangement of the complete
set of 25 cards by matching equivalent fraction expressions. After the pupils had
completed ‘the jigsaw’ the teacher asked individual pupils to choose some of the
matching pieces and explain why they showed equivalent fractions.
Fractions Jigsaw from the NRICH website http://nrich.maths.org. © University of
Cambridge. Used with kind permission.
© Crown copyright 2011
Teaching and Learning Resources p.2
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Pupil D's work
Pupil D started this activity by claiming: ‘I can't do fractions, they don't make sense.’
However, he was determined to complete the jigsaw and quickly became engaged
with the task.
Before doing the activity, he had the common misconception that adding (or
subtracting) fractions involved adding (or subtracting) the numerators and the
denominators; for example,
5
8
−
1
4
=
4
4
.
5
1
4
3
During the activity, however, when the teacher asked him if 8 − 4 was 4 or 8 , he
responded confidently: ‘You can't take away like that, you have to have the bottom
numbers the same, it's really like
© Crown copyright 2011
5
8
−
2
8
so the answer is
3
8
4
not 4 .’
Teaching and Learning Resources p.3
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He recognised that his completed jigsaw had errors, but said that he was pleased
with the activity because: ‘I know how to do fractions now.’
© Crown copyright 2011