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- Calculations with larger numbers


In this class of 4-5 year-olds (in a mixed nursery and

reception class) , the teacher had been reading

'One is a snail, Ten is a crab' (Pulley Sayre, Sayre

& Cecil, 2004), to support the children's counting up

to 100.

      She suggested that the children choose their own 

number, and work out which combination of

creature's legs would total their number.

    Roxy decided on '67', explaining "it's a big

number, so I'll do crabs because they have the

most legs. Ten, twenty, thirty, forty. That's four

crabs." Drawing two more crabs she again counted

in tens. Explaining that she needed seven more

she drew three people, finally adding a snail,

writing her calculation in words at the foot of the page.




Trees explained that he was going to work

out 800, after a while explaining he had four

crabs and four snails: "That's not the eight 

hundred! Need loads more so I think I'll do

more crabs 'cos they've got the most legs." 

Adding addition crabs and snails he counted

to 104. Pausing, he decided, "I don't think I'm

going to do any more because it's too big. I

need six more so I can do six snails, or a dog

and two snails, or three people -but I'm just

going do a fly because it has six legs."

    The teacher described the children's

graphical responses as "a real eye-opener",

their self-challenges and problem solving

as "remarkable!"


Chang's class were going on a residential trip,

and their teacher had bought some nectarines. 

She invited the children to work out how many

packs (with three in each pack) she would need

to buy so that 26 children could have one each.

Chang (7 years 1 month) responded by counting

in threes and noting that there would be one

nectarine left over (which the children suggested

their teacher could have)!

Harriet (7 years, 4 months) tackled the same 

problem, drawing 'packs' with three children

in each, and crossing out the surplus person

in the last pack, then writing '9' beneath.

Earlier she had drawn another pack but

realising she did not need it, had crossed it


     Self-checking can indicate reflection and

efficient levels of thinking.