Stage: 1 Challenge Level: 
Do you think the lengths of the lines mean something?
Why do you think some of the drawings have curved lines?
What are the similarities and differences between the drawings?
Odd and even numbers. History of number systems. Visualising. Factors and multiples. Interactivities. Counting. Games. Reading and writing numbers. Working systematically. Addition & subtraction.
Published November 2009,December 2009.
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