Introduction to decimal symbols with box

Montessori Introduction to the Decimal Symbols: A sensorial material to associate symbols with quantities and prepare for handling large numbers.

MATERIAL OVERVIEW:

• 1 tray divided into four compartments:

- on the right of the tray there are 9 beads

- to the left of the 10 beads there are 10 tens

- to the left of the 10 tens there are 10 hundreds

- to the left of the 10 hundreds there is a cube of 1000

• a box of "small" symbols ranging from 1 to 9, from 10 to 90, from 100 to 900 and stopping at one thousand (not included).

PRESENTATION:

1. on a mat placed lengthwise, lay out the units on the right one below the other, following the order of the sequence. To the left of the units, arrange the tens in a column and in order, then to the left of the tens the hundreds, and to the left of the hundreds the thousand.
2. on the other mat, which you will have taken care to set away from the first, lay out the 10 beads lengthwise on the right. Then to the left of the 10 beads the 10 tens one below the other, then to the left of the tens the 10 hundreds and finally the cube of 1000.
3. ask the child if they remember what it is and point to the bead: (one unit), do the same for the bar, the hundred and the cube. Likewise check whether they remember the numerals. Then take the tray, place the number 300 in it and ask the child to go and fetch the equivalent quantity. Once the child has brought back the quantity, ask them to count what they have put on their tray. (One hundred, two hundreds, three hundreds, you have brought back three hundreds)
4. once the child has become familiar with a single number being given to them, offer them two numbers; place on their tray, one above the other, the number 40 and the number 4. Ask them to count what they have brought: one, two, three, four tens and one, two, three, four units. You have brought back four tens and four units.
5. then offer them the number 600 and below it the number 1. Proceed in the same way. If the child seems comfortable, offer them three categories, place for example 300 then below 70 then below again 8. Ask the child to count what they have brought; 1, 2, 3 hundreds, 1, 2, 3, 4, 5, 6, 7 tens and 1, 2, 3, 4, 5, 6, 7, 8 units.
6. then offer four categories, for example 1000, below 200, below again 40 and below 6. Ask them what they have brought and ask them to count. Tell them that you are going to show them something, the "magic game". Place 1000 on the mat, below it 200, below the 200 place 40 and below the 40 place 6. Place 200 over 1000, putting the 2 over the 1, then 40 over the 200 and 6 over the 40. The number that appears is 6000. Take all the tickets in one hand and slide them all to the right; the number 1246 appears. Invite the child to do it in turn. Once the child is at ease, offer them the reverse search: starting from the quantities, ask them to go and take the corresponding number.