Stage: 2 and 3 Challenge Level: 
What numbers can you
make? Do they have anything in common?
Have you made $37$ with a different number of numbers? How many? Do
these numbers have anything in common?
What do you notice about the numbers in the bags?
Addition & subtraction. Visualising. Working systematically. Creating expressions/formulae. Generalising. Mathematical reasoning & proof. Area. Odd and even numbers. Interactivities. smartphone.
Published October 2003.
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