12 disc
Fraction discs
Resources
 Fraction disc cards (An A3 enlarged 12 disc will be useful and
groups of children should have a set of 4 postcard-sized cards.
 Blank discs (possibly enlarged)
 Paper for recording
 Some teachers will find it useful to have a set fraction calculation
problems. (pupils can also be encouraged to set and solve own
problems, designing own disc)
Fraction discs:
Teacher notes
As children become fluent solving simple problems with the 12 disc, a Mini
plenary is useful.
 Ask why the 12 disc is good for thirds, quarters, halves, sixths, twelfths?
 Ask whether the 12 disc would be good for doing calculations with halves
and fifths.......What disc would be good for these?
 Prepare some other discs (10-disc, 8-disc, etc) and let children use these
to build the idea of which disc to use.
[e.g. What fractions would the 8 disc be good for?, what disc would be
good for problems with quarters and fifths?.... ]
 Protractors - if accuracy is needed - but pupil jottings are usually
sufficient.

Use”12 disc” as starter activity with whole class
 Name any fraction and ask a child to explain why this much of the
disc represents that fraction.
 Suggest that children think of a problem that none of the discs they
Look for answer, for example, that a third of 12 is 4, so a third has 4 slices,
etc.
 Do this with the all the fractions.
 Model an addition fraction using the disc. [e.g. one third add one
quarter]. Ask a few similar addition problems.
 Set a subtraction problem [e.g. one third minus one quarter]. Ask
similar problems.
Allow pupils some time to work in pairs using these discs to solve
a few calculations..... and maybe to generate and solve some of
their own problems.
have will solve..... why? What new disc would be useful now?
 Give out some blank discs and ask pupils to mark this with
fractions needed and solve problems with it.
Discs can be drawn accurately but good working sketches may be just as
useful and easier for children without construction skills.
 Remind pupils of the kind of problems can be solved using discs.
Add / subtract fractions
 Ask how you decide which discs to use.
 Pose some further problems. Which disc? Why?
 Children will have been working with common denominators,
equivalent fraction addition, etc but without the complexities that
usually surround these...and most will have been successful!!
 Transferring to these standard methods will now be built on firmer
conceptual understanding.