The Cuisenaire Gattegno Method Of Teaching Mathematics

different colors (or of the same color) which when added to the yellow rod make a length equal to that of the blue rod’. The term ‘difference’ was then introduced and experiences provided with ‘which rod makes up the difference between the yellow and the blue rods?’ This was simplified in time to ‘find the difference between 5 and 9’. The third step developed the ability to express subtractions in written form and involved the use of the sign for ‘minus’. Pupils should realize that the activities carried out in each of these three steps are the same, in other words, that ‘What must be added to 56 to make 72?’ is equivalent to ‘72 minus 56’. 2

The notion of equivalent differences

The second point developed in this course is the idea that subtractions form families, that there is an infinite number of subtractions that have the same difference; for instance: 5=5–0=6–1=7–2=8–3=... Experience of this fact is given because it forms the basis of the method to be employed in the operation of subtraction. It enables pupils to transform ‘hard’ subtractions into easy ones, to use 17–10 when faced with the equivalent difference of 16–9, to use 76–30 for 73–27, and 918–700 for 905–687. 3

Developing informal methods of subtraction

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The Cuisenaire Gattegno method of teaching Mathematics

The Cuisenaire Gattegno method of teaching Mathematics

The Cuisenaire Gattegno method of teaching Mathematics

The Cuisenaire Gattegno method of teaching Mathematics