Group operations Dynamic addition (with change)

What does the word “Dynamic” mean in Montessori?

“Dynamic” in Montessori means an exchange will need to be made. This activity is very much the same as static addition with the Golden Beads, the only difference with this one is there will be an exchange.

The directress usually works with a group of children, where one child lays out the Large Number Cards on one mat, another child lays out the Small Number Cards on another mat and another child lays out the Golden Beads on another mat.

The directress comes up with a sum, made up of the smaller number cards, for example, 236 (the first number). The child goes to the banker to collect the correct amount of beads for that number.

She comes up with another number made up by the Small Number Cards, for example, 125. The child repeats in the same manner as before and goes to collect the correct amount of beads from the banker for that number.

The directress asks the children to start adding the numbers together by beginning to count the units. On reaching ten units, the directress will say: “these 10 units can be exchanged for 1 ten-bead bar”. The children put the units into a changing bowl to exchange them for one ten-bead bar. The child brings back the ten-bead bar from the banker and places it next to the other ten-bead bars of the first number. The child is then asked to count the remaining units and to fetch the Large Number Card to represent how many units are left.

The child goes ahead and counts the tens and hundreds, finding their corresponding Large Number Card. The directress finishes the lesson by overlapping the cards and telling the children that ‘when we take 236 and we add 125 we get 361’.

What skills do children acquire by doing this activity?

This is a wonderful activity for children to develop their mathematical minds, it helps children practice counting and it is a wonderful introduction to show the children how we exchange to higher hierarchies.

Looking for more Montessori activities?

Here is a list of all the Montessori Maths activities including Early Maths, Introduction to the Decimal System, Seguin Boards, The Hundred Board, The Short Bead Stair, Bead Chains, The Snake Game, Group Operations, The Large Number Rods, Recording with the Small Number Rods, The Short Bead Stair, The Strip Boards, The Boards, The Stamp Game, The Abacus, The Dot Game, and Fractions. Just click on the page you want to learn about to go there.