# Bead Bars: Breaking Down the Addends

From wikisori

## Contents

### Age

6-9.

### Materials

- Ten bars
- Colored bead bar
- Box of signs for operations

### Preparation

### Presentation

- On a strip the directress writes a combination of two or three numbers.
- The child constructs the problem with bead bars and symbols and computes the answer and puts out the corresponding bead bars for the sum.
- The child reads the equation.
- The directress lays out combinations in parentheses that equal each addend of the first problem, i.e. 1st 9+7+8= 24, 2nd (4+5) + (3+4) + (6+2) =
- The child computes this as before, adding the first two addends in parentheses, placing the bead bar for the sum below, etc.
- Those three are added again to obtain the same answer as before.
- It is noticed that the first and third equations are identical.
- In the second, each addend was broken down into two smaller addends.

### Control Of Error

### Points Of Interest

### Purpose

- To give the concept of the dissociative property of addition.

### Variation

### Links

### Handouts/Attachments