# Subtraction

SUBTRACTION

Purpose:
To give the children the experience of the process of subtraction.
MINUEND – SUBTRAHEND = DIFFERENCE

Materials:

Control:
The teacher. However, the emphasis is on the process not on the correct answer.

Age:
5 years

Presentation:
A small group exercise.
Layout as for addition and multiplication.

Static Subtraction:
Select a high number in the large number cards and the corresponding amount of golden bead material (minuend).
Place the golden bead in hierarchical order in the center of the work area.
Place the large number cards at the top right corner of the mat.
Select a low number in the small number cards and place them on a child’s tray (subtrahend).
Tell him he may take that quantity from the golden bead on the table, beginning taking from the units. He proceeds in this way until he has taken the quantity specified in the small number cards on his tray.
The teacher then states the quantity that is left on the table and asks a child to find the small number cards and place them below the beads (difference).
Review the process and place the small number cards from the child’s tray (subtrahend) below the large number cards (minuend) and place the small number cards representing the difference, below the subtrahend.
State, now we have done ‘subtraction’.

Dynamic Subtraction:
This can follow when the child understands the process of subtraction.

Individual Work:
The child can take the tray of golden bead and work at his table or he may take what he needs from a ‘pool’ of golden bead material.

EXERCISE 1: As in the presentation.

Presentation & EXERCISE 2: Minuend of 9000
(When the child has mastered Exercise 1.)
Select a minuend of 9000.
Proceed as for dynamic subtraction showing the child how to exchange a thousand for hundreds; a hundred for tens and a ten for units before he can begin subtracting.