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Why do this
challenges learners to think about the
construction of the familiar hundred square and about the first
hundred numbers in our counting system. It consolidates
understanding of place value and promotes useful discussion between
pairs of learners working together as they will have to conjecture,
explain and justify their ideas.
You could introduce this problem first by asking the group to
picture a hundred square in their mind's eye. Challenge them to
answer questions orally such as:
- What is immediately below $10$? [$20$]
- What is two squares to the left of $99$? [$97$]
- I start on $34$ and move three rows down and three places to
the right. What do I land on? [$67$]
Each time, invite children to explain how they came to a
solution. You may like to ask some learners to post their own
challenge for the rest of the group. It may be that some children
will want to refer to a paper copy of a hundred square to check
their responses, but don't actively encourage this!
You can then present the problem itself, ideally on the
interactive whiteboard, and ask pupils to work in pairs so that
they are able to talk through their ideas with a partner. They
could either use the interactivity on a computer or cut out the
pieces from these two printed
At the end the group could discuss how they discovered the
clues needed to put the whole together and what they learnt about
the construction of a hundred square. It is interesting to see the
number of different ways adopted - each one just as valid as the
others. The important point is being able to justify why one piece
goes in a particular place. You may decide to highlight the value
of talking with someone else while working on this task. How did it
Where could we start?
What might the first numbers look like?
What might the last number look like?
What do you know about the multiples of $11$?
What will be the same in each column?
What will be the same for the first nine numbers in each
Learners could either try
which introduces different bases or
which looks at numbers in different
Some children may benefit from having an ordinary hundred square to
refer to as they work on this problem. It might help to try this
Hundred Square Jigsaw
first, but be aware that this one goes
from zero to ninety-nine, not one to a hundred.