The Cuisenaire Gattegno Method Of Teaching Mathematics

(520 – 8) ÷ 16 = 520 – (16 × 32) =

(520 — 8 ÷ 64 = 520 – (4 × 128) =

Multiplying And Dividing By 2 Teachers will find it essential to spend time developing the skill of doubling and halving until the pupil masters multiplication and division by 2 in the range of numbers up to 1000. It must be emphasized that he should not yet be shown any formal or fixed process for these operations. In exercise 14, Part IV of Book II of Mathematics, when reaching 96 in the series of doublings from 3, he is deliberately shown two informal methods: 2 × 96 = 2 × (90 + 6) = 2 × 90 + 2 × 6 = 180 + 12 = 192 = 2 × (100 – 4) = 2 × 100 – 2 × 4= 200 – 8 = 192 And when doubling 192 he is encouraged to say 2 × 192 = 2 × (190 + 2) = 2 × 190 + 2 × 2 = 380 + 4 = 384 Similarly, when halving 384, for example, he could possibly say that of 384 =

of 300 +

of 84 = 150 + 42 = 192

It is also to be noticed that Gattegno does not follow up these initial exercises in multiplying and dividing by 2 with a series of

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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