What is abacus. How it is used for doing math calculations by children with visually impaired. pre requisite needed for mastery in mathematical brille code. Adaptations and improvisation of teaching aids in maths. Need for TLM out of waste materials.
procedures of setting number and prerequisite for learning abacus
1. Braille and Assistive Devices
Dr.S.Revathi
Asst.Professor,
Dept. of Special Education
UNIT-4
2. Abacus and Geometry Kit
• 4.1Setting numbers
• 4.2Setting addition and subtraction
• 4.3Setting of Multiplication
• 4.4setting of division
• 4.5Teaching Geomentry using Geometry kit
3. Mastery over Mathematical Braille
Code
• Teaching of the code should start from the primary
level itself. As soon as the child learns writing,
strenuous practice in writing mathematical codes is
to be given. Since experiences have shown that
visually impaired children show resentment to learn
mathematical codes when they are introduced at a
later stage, say, directly at the secondary level, the
teaching of these codes should take place in a phased
manner from the very beginning of the child’s
schooling.
4. • It is not necessary to teach all mathematical
codes at a time. Suppose 15 codes are to be
taught at the III Standard, these can be taught
as and when they are required in the lesson.
This way of introducing the appropriate code
at the appropriate time makes the learning
spread out throughout the year and it will be
more meaningful to the child.
5. • When the child is through with the writing of
the code after the writing practice, a small
passage can be prepared in mathematics and
the child be asked to read it. This is treated
most essential because the child should know
how to discriminate the mathematical Braille
code from the literary code while reading. This
practice should be continued until the child
gets mastery over the usage of that code.
6. Adaptation of the Mathematics
Text Material
• In the process of providing substantial
learning experience to children with visual
impairment, it is advisable to keep the
expected outcomes on par with sighted
children and adapt/substitute learning
experience to derive maximum understanding
of the concept. Take for example, the concept
of “Rows and Columns”, an effective teacher
will be able to create a lot of situations to
explain this concept to the child.
7. • In fact, the cells of the Braille slate can be
used to explain this idea; the Geo-board can
be used, the seating positions of the children
in the class itself can be used to explain this,
tactile graph sheets can be used and so on.
Even though it is primarily true that certain
concepts are seen and understood, the fact
remains that most of the concepts could be
modified to suit the needs of the visually
impaired child.
8. Development of Mental Arithmetic
• The mental ability of doing mathematical
calculation is the result of concentration and
mastery over the basic mathematical
operations.
9. IMPROVISATION OF
TEACHING AIDS IN MATHEMATICS
• Teaching aids are of many types. There are
sophisticated aids, teacher-made aids and
even some other real objects and materials of
the environment which can be used as
teaching aids. Whatever might be the aid, the
usability of it depends on the nature and need
of the learner, the emphasis the teaching aid
lays on learning the concept and the ability of
the instructor to make use of the teaching aid
to the maximum extent
10. • Secondly, the education of visually impaired
children warrants more varieties and, as a
result, a maximum number of teaching aids
would be required. The teacher should know
the techniques of using available resources
which can provide maximum simulating
experiences to the visually impaired child.
11. Wealth from Waste
• In a normal school environment, many things
which are usually treated as waste can
effectively be used as teaching aids for visually
impaired children because what they feel is
more important than how the teaching aids
look like.
12. • For example, a waste chalk box can be used to
explain the concept of a cubical; a rubber ball
can be used for explaining the concept of a
globe; different plastic balls can be used to
explain the concept of volume; the chalk bits
and stones can be used for counting; the
Braille book itself can be used to explain the
concept of rectangle/square; the waste
cardboards can be used by the teacher to
prepare cut-outs of triangles and various
geometrical figures and so on. Making wealth
from waste depends on the creativity of the
teacher.
13. Three-dimensional Aids
• There is no doubt that three-dimensional aids
would give concrete experiences to the
visually impaired child in understanding a
specific concept.
14. • The following principles are very important for
the selection of three-dimensional teaching
aids:
• i. The three-dimensional teaching aid should
be handy. It should not be too big to explore or
too small to understand the minute
differences.
• ii. It should be strong and sturdy so as to
withstand the manipulation of the visually
impaired child.
15. • iii. As far as possible, sharp edges should be
avoided in three-dimensional aids for visually
impaired children. Sharp edges may be made
blunt to avoid injuries to the Braille reading
fingers.
• iv. If the teaching aids are of collapsible type,
understanding will be better. For example
concepts like hemisphere, diameter,
circumference, radius, etc., can also be
explained when the globe is of collapsible
type.
16. Abacus
• Abacus is a device used by visually impaired
children for doing basic mathematical
calculations. Abacus is rectangular in shape
Abacuses with varied columns are used in
different countries. But we are using abacus
with 15 columns.
17. • Setting
• The process of moving a bead of the lower
abacus or the upper abacus towards the
separation bar is called ‘setting’.
• Clearing
• The process of moving a bead away from the
separation bar either towards the top of the
upper abacus or the bottom of the lower
abacus is called ‘clearing’.
18. • Dots in the Separation Bar
• The dots in the separation bar are helpful for
locating the place values of numbers in abacus
19. PRE-REQUISITE SKILLS FOR THE
EFFICIENT LEARNING OF ABACUS
• Abacus should be introduced as early as
possible in schools. However, those children
who did not have an opportunity to learn the
skills at the primary level can also learn those
at a later stage. For such children,
understanding as well as mastery in certain
mathematical concepts would enhance the
effective learning of operations through
abacus
20. • 1. Demonstrating the correct finger movements in
using abacus.
• 2. Demonstrating correct hand positions in using
abacus.
• 3. Explaining the counting procedures in abacus.
• 4. Explaining the concept of Clearing and Adding in
abacus.
• 5. Understanding the concept of Complement of
certain number with respect to another number.
• 6. Memory of Multiplication tables for numbers 1 to
20, preferably for higher classes.
21. • Memory of the squares of the numbers 1 to
25 (minimum), preferably for higher classes.
• 8. Memory of the square roots (perfect) of
squares from 1 to 1000, preferably for higher
classes.
• 9. Understanding the relation between
fraction division and fraction multiplication.
• 10. Understanding the concepts of Least
Common Multiple and Highest Common
Factor
