Abacus Lesson 9 // Addition -Complementary Numbers Respect to 5- ONE'S Column

Short easy lessons paced for younger viewers that teach addition and subtraction on a traditional abacus or soroban.

PLEASE READ THE DESCRIPTION BELOW FOR A LESSON MAP.
*Download the FREE worksheet that goes with each lesson.*
http://thehevproject.blogspot.com/p/f...

The abacus uses complementary numbers for calculation. In order to become familiar with the process, the lessons are broken down into the following 7 sections:

1- Lessons 1-2. Introduction to the Abacus.

2- Lessons 3-8. Simple Addition. This is REALLY simple math and does not involve the use of complementary numbers. MOST OLDER STUDENTS WILL BE ABLE TO SKIP THESE LESSONS once they are comfortable with moving the beads.

3- Lessons 9-11. Addition using Complementary numbers with respect to 5.

4- Lessons 12-17. Simple Subtraction. This is REALLY simple math and does not involve the use of complementary numbers. MOST OLDER STUDENTS WILL BE ABLE TO SKIP THESE LESSONS once they are comfortable with moving the beads.

5- Lessons 18-20. Subtraction using Complementary numbers with respect to 5.

6- Lessons 21-27. Addition and Subtraction using Complementary numbers with respect to 10.

7- Lessons 28-33. Addition and Subtractions using COMPOUND Complementary numbers with respect to 10. This is where you really start using the abacus. These lessons are the most challenging for students at any age. (a lot of people give up here)
Make sure you have a solid understanding of complementary numbers with respect to 5 and 10 before attempting these lessons.

-------------------------
The abacus is emerging as a re-discovered treasure in teaching children basic math. It is the original calculator and is still used in many parts of the world.

Some ways that children benefit by learning the abacus are:

-Visual representation of the number system.
-Properly lining up numbers for addition.
-Number placement and values (including decimals)
-Whole brain development. Promotes the right brain development of visualization and the left brain development of logic and calculation.
-Improved mental calculations

The abacus is fun and clicks instantly with children of any age.

Each lesson involves a short 7-10 min instructional video that teaches the fundamental principles behind the subject being taught with printable activities sheets to help with learning the abacus.

You will need an abacus to do this course. Here is a link to where we purchased the abacus used in the video. (You can use any abacus so long as it has the same parts as the one shown in the video)
The place I originally got the abaci from no longer sells them, but here is a place that sells a similar one. Please report if this link is no longer valid so I can up date this :)
http://www.suntekstore.com/goods.php?...

Ages: All ages. As soon as a child learns to count on their fingers they are ready to start using the abacus. However, ages 8 and up will benefit the most. Older kids will already be comfortable with basic math skills and will feel that these videos move a bit slow, but can still benefit significantly by learning the abacus.

Lessons should be done in order as each lesson builds upon principles from the previous lesson.