IFIT Montessori

3-6

Materials

1. A number line board with numbers 1 to 18.
2. One set of number strips from 1 to 9 in red.
3. A Blank Strip.
4. Subtraction Cards with examples of subtraction questions with minuends of up to 18.

Preparation

Presentation

1. Directress builds the strips on the board. from the work card, e.g. 9-5.
2. Directress takes the Blank strips and covers after 9.
3. She then takes a 'five' strip and places it next to the blank strip on the board.
4. "How many left?"
5. Then she counts the number of squares left uncovered, i.e. 1, 2, 3, 4.
6. Then the Directress says "Nine minus five equals four".
7. Directress also points out that the answer can be obtained by looking at the answer stated on the top row of the board.
8. Encourage the child to work through the questions on the work cards and records his answer.

Control Of Error

The numbers on the board act as a Control of Error.

Points Of Interest

Purpose

• To give the child further experience in subtraction and to extend the subtraction activity up to 18.