Substraction with Small Number Rods
From wikisori
Contents
Age
3-6
Materials
- Two sets of Small Number Rods.
- Plain squared paper and a pencil.
- Subtraction Sign Card (optional).
Preparation
Presentation
- Directress invites the child to build two stairs with the number rods.
- The Directress selects a rod from the right stair, says a 4 rod.
- Then she asks the child to select a rod shorter than 4 rod from the left stair.
- The child selects 2 rod and places it besides 4 rod.
- The Directress invites the child to count together, "1, 2, 3, ... 6.
- Four and two makes 6. Let's take away 2 (Directress removes 2 rod). How many left? 1, 2, 3, 4. (count). 6 takes away 2 equals 4"
- Directress then shows the child how to record the statement on plain squared paper, i.e. 6-4=2.
- Directress may go on with the presentation by showing a few more examples.
Control Of Error
The rods themselves act as Control of Error because the quantities are fixed.
Points Of Interest
Purpose
- Introduce the child to Subtraction situations with answer (differences) under 10.
- Show the child how to record subtraction questions with answers under 10.
Variation
You may use only 1 set of Rods. For example: 6-4=2.
Select 6 rod. Count from the right end 1, 2, 3, 4 and cover those with your fingers. The answer is those left uncovered, which are 2.
Handouts/Attachment