B.Ed.
Teaching Notes
Theoretical
bases of teaching physical science
Unit
2 - Methods and Techniques of Teaching Science.
Prepared by
SABARISH-P
M.Sc., M.Ed., JRF & NET
Assistant Professor in Physical Science, Arafa Institute for Teacher Education
Attur, Thrissur.
Teaching
techniques and strategies
Ø Brainstorming
This is a strategy for generating
ideas. In a classroom, the teacher can
select a problem-oriented topic and ask the students to express themselves
freely on various aspects of the topic.
The teacher assures the students that their expression will not be
criticized or commented upon a negative way.
The views/opinions of the participants would not be viewed as relevant
or irrelevant but the students are encouraged to come out with their ideas,
opinions, feelings, expressions and comments.
Brainstorming, founded in 1953 was popularized by A.F.Osborn.
Procedure
Brainstorming is an instructional
procedure similar in many ways to an exploratory discussion. Brainstorming is used to generate a wide
variety of creative ideas concerning a problem in a short period of time. The major purpose is to stimulate thinking and
bring out a range of ideas. Students are
encouraged to come up with exciting and radical ideas without fear of criticism
or evaluation. The strategy is easily
operationalised.
·
Divide the class into small groups
consisting of 5 to 8 members. Let them
select a record and a chairperson.
·
Explain the basic rules of
brainstorming.
·
Present the issue to be
brainstormed. The recorder should record
all ideas. Brainstorming does not
include critical judgement and/or editing of ideas.
·
At the first stage of brainstorming,
even far out or wild ideas are also accepted.
·
After students have had sufficient time
to generate ideas, list all ideas on a chalkboard.
·
A number of creative activities can be
framed out of the brainstorming session such as presentation, discussion of
ideas and making bulletin board displays.
For encouraging creative thinking and
co-operation, brainstorming is an excellent strategy.
Guidelines for using brainstorming
1. Identify the problem or issue to be
brainstormed and present it in simple language.
2. Write everything down; do not judge it
or evaluate the ideas.
3. Consider using more than one recorder
so that no ideas are lost.
4. Emphasize some basic rules, which
should be enforced.
Stages in brainstorming
1. Warm-up
:Attracting the members to the subject, arousing their interest and preparing
them for free expression is the first stage.
This is the duty of the anchor.
The teacher can act as the anchor at the beginning to give an idea of
this role to the student. The warm-up can
be done through the narration of an appealing incident or a short story.
2. Ideation:
This stage is of free expression of ideas.
Ensure that all ideas are recorded.
3. Evaluation
: In this stage, ideas expressed are evaluated. Using the criterion formed through
discussion, each idea is evaluated and the appropriate idea for problem solving
is found out.
Principle of brainstorming
Brainstorming, to become effective
is carried out on the basis of four principles.
a. Free wheeling : Once started, the brainstorming
session should progress like the lubricated wheel. That is, expression of opinions should be
possible without interruption. The idea
may irrational, comical or strange. But
all such ideas may be accepted.
b. No criticism : It must be ensured that
expressions and gestures do not reflect a critical attitude.
c. Quantity breeds quality : The more
number of ideas generated, the number of qualitative ideas alos increase. Hence maximum number of ideas should be
collected. Each person may be given
opportunity to present ideas agian.
Prompting those students who remain silent, without hindering others is
the duty of the anchor.
Rules
1.
No judgement or evaluation of ideas
2.
The sky is the limit. (thinking is unlimited)
3.
The more ideas, the better.
4.
Keep the brainstorming process informal and relaxed.
5.
Record all ideas.
6.
Use brainstorming when a lot of ideas are needed, or when time is
limited.
Merits
1.
It makes the pupil creative and innovative.
2.
It gives opportunity for pupils for analyzing and solving a problem.
3.
Useful in problem oriented themes.
4.
Recording of all ideas of pupils is considered.
5.
Encourages participation and can be used by all students.
Demerits
1.
Difficulty in selecting a problem oriented topic
2.
Problem of discipline
3.
Lack of adequate library and laboratory
4.
Finding out a tentative solution is challenging.
Ø Questioning technique
"Good
learning starts with questions, not answers"
Questioning consumes a
considerable proportion of time in classrooms. Interest in questioning as an
instructional tool can be traced back to the fourth century as evidenced in the
Socratic dialogues recorded by Plato.
In the 21st century,
teachers use questions to manage student behavior and classroom activities, to
promote students' inquiry and thinking, and to assess students' knowledge or understanding.
Questioning enables teachers to check learners' understanding. It also benefits
learners as it encourages engagement and focuses their thinking on key concepts
and ideas. Questioning actively encourages the development of thinking and dialogue
skills.
Questioning can serve
at least 5 distinct purposes in effective classrooms.
1. To guide students toward understanding
when introducing material.
2. To guide students to do a greater share
of the thinking.
3. To remediate an error.
4. To stretch or motivating students.
5. To check for understanding (Evaluation
purpose).
In questioning
technique teachers uses questions as a tool to promote inquiry, thinking, and
ultimately learning.
An effective question
must involve the following techniques
1)
Redirection:
This involves the framing of a single question for which there are many
possible responses from the students. Redirection is possible only in the case
of high order, divergent questions.
Example:
At the end of this unit Halogens, which do you think is the most useful one?
………….Why?
2)
Prompting:
This
technique involves the use of hints or clues which are used to aid the student
in responding correctly. This is required when a student is asked a question
and he fails to reply or response correctly.
3)
Probing:
This technique is used when the students reply is correct but insufficient
because it lacks depth. This helps to process information.
Thumb
rules of effective questioning
A few general rules of thumb for designing effective
questions are:
1)
One
at a Time: Have only one question in the question.
2)
Simple
to Complex: Ask questions that progress from simple
to complex.
3)
Clear
and Concise: The questions should be clear and
Concise
4)
Start
with a question word. (who,
when, what, where, why, how)
5)
Ask
an actual question.
6)
Assume
the answer. (Ask, “Who can tell me…,”
not, “Can anyone tell me…”
7)
Stock
Questions: Ask one sequence of questions in a
row. Ask versions of the same question.
8)
Break
it down: Break
complex questions to simple, one after the other.
Ø Buzz Session
In buzz sessions, we allot a fixed
amount of time for the students to discuss a problem or a task in a small group
(in pairs, or in threes). Clear
instructions may be given so that the discussions are productive. The efficiency of such a session would be
enhanced by the teacher moving around and getting a feel of the discussions
without interrupting. Once the small
groups finalise the solutions to the problem, the representative of the group
reports back to the teacher. The teacher
has to compile all the reports and provide his judgement to the students.
Buzz session can be organized in a
regular class of large strength or form group among the students and ask the
groups to take their leisure time to discuss their problem and report back to
you. This is called “Buzz session”
because group “buzz” like bees while
discussing the problem.The uniqueness of Buzz session is that it is useful in
deriving creative and innovative solutions to tasks and problems.
Merits
1. Develops classroom interaction
2. Gives training the discussion
3. Teacher becomes an active participant.
4. Develops skills among pupils.
Demerits
1. Time consuming.
2. Difficulty in forming groups in class.
3. Most of the students lack
initiativeness.
Ø SMALL GROUP TECHNIQUES
“A group” in a class comprises of members
having common academic goals, similar academic background and more or less
similar age.
Small group techniques of providing
group-controlled learning experiences are:
1. Buzz Session
2. Brain Storming
Ø Distinction between Buzz Session
and Brainstorming
|
Buzz Session
|
Brain storming
|
|
There
is criticism of ideas presented by members
|
No
criticism
|
|
Members may not
express their ideas freely
|
Members
can express their ideas freely
|
|
Controlled
by supporteurs
|
Controlled
by anchor
|
|
Group size 5 or 7
|
Large
Group
|
|
Time consuming since
there is discussion of unsolved problems
|
Less
time is required compared to Buzz session
|
Ø Debate
Debate is a method of presentation
especially suitable to controversial themes and for developing skills like
logical arguments. The participating students could be divided into two groups,
one for proposition and the other against it. Teacher can act as a moderator.
Merits
1) Develop
argument abilities
2) Promotes
leadership qualities
3) Increases
communicative skills
4) Supports
creativity
Demerits
1) Lack
of interest among pupils
2) Difficulty
in forming identical groups
3) All
topics cannot be covered.
4) May
create emotional and personal criticisms.
Ø Symposium
Generally called as a
conference or meeting to discuss a particular subject. In this a topic is broken into various parts. Each part is presented by
an expert or well-informed person in a brief concise speech. The facilitator
meets with 3or 4 group members and plans an outline. At the end the facilitator
summarizes the main issues.
Ø Panel Discussion
A
panel discussion is a specific format used in a meeting, conference or
convention. It is a live or virtual discussion about a specific topic amongst a
selected group of panelists who share differing perspectives in front of a
larger audience.
A
panel discussion, or simply a panel, involves a group of people gathered to
discuss a topic in front of an audience, typically at scientific, business or
academic conferences, fan conventions, and on television shows. Panels usually
include a moderator who guides the discussion and sometimes elicits audience
questions, with the goal of being informative and entertaining.
The
definition of a panel discussion is a situation in which a group of people are
gathered together to discuss an issue, often to provide feedback on something,
to formulate solutions to a problem or
to discuss an issue of public concern in front of an audience.
An
example of a panel discussion is a TV focus group where a group of viewers are
assembled to give feedback to the producers on the show.
An
example of a panel discussion is when top scientists gather together to discuss
global warming.
An
example of a panel discussion is when a group of local politicians hold an open
discussion and invite the public to come with questions or concerns.
The
panel is typically facilitated by a “moderator” who guides the panel and the
audience through the event.
The
panel, typically 3-4 experts or practitioners in the field, shares facts,
offers opinions and responds to audience questions either through
questions by the moderator or taken from
the audience directly.
The
panel session typically lasts for 60-90 minutes.
Use
a panel when you believe the group of panelists will generate something more
interesting than any one individual panel member could generate on his/her own.
Ø Seminar
It is an instructional
technique which involves in generating a situation for a group to have a guided
interaction among themselves on a theme.
A seminar may be defined as a
gathering of people for the purpose of discussing a stated topic. Such
gatherings are usually interactive sessions where the participants engage in
discussions about the delineated topic. The sessions are usually headed or led
by one or two presenters who serve to steer the discussion along the desired
path.
PURPOSE OF A SEMINAR
A seminar may have several purposes
or just one purpose. For example, a seminar may be for the purpose of
education, such as a lecture, where the participants engage in the discussion
of an academic subject for the aim of gaining a better insight into the
subject. Other forms of educational seminars might be held to impart some
skills or knowledge to the participants. The participants gain knowledge or
tips about the topic of discussion.
A seminar can be motivational, in
which case the purpose is usually to inspire the attendees to become better
people, or to work towards implementing the skills they might have learned from
the seminar. For instance, a business seminar with a financial theme could be
for the purpose of teaching small business owners how to pitch to investors or
to write a solid business plan, and to motivate them to get started right away.
PLANNING A SEMINAR
The first step towards planning an
effective seminar is to determine what the purpose of the seminar will be.
Think about the target audience who will participate and what they stand to
gain from attending the seminar. Every seminar must have an agenda, so
determine what the agenda will be. Set a budget for the seminar and work within
this budget.
Merits
1) Spontaneous
learning occurs
2) Useful
for sharing large information
3) Learning
experience is highly structured by the learner himself.
4) The
teacher or chairperson of technical session only plays the guidance.
5) Learner
gets in-depth knowledge of the subject he presented
Limitations
1) Every
topic is not feasible
2) Suitable
for higher classes only.
3) Limited
scope for learning by doing.
Ø Concept map
Concept maps graphically illustrate
relationships between two or more concepts and are linked by words (Link words)
that describe their relationship.
Used as a learning and teaching
technique, concept mapping visually illustrates the relationships between
concepts and ideas. Often represented in circles or boxes, concepts are linked
by words and phrases that explain the connection between the ideas, helping
students organize and structure their thoughts to further understand
information and discover new relationships. Most concept maps represent a
hierarchical structure, with the overall, broad concept first with connected
sub-topics, more specific concepts, following.
Definition
of a Concept Map
A concept map is a type of graphic
organizer used to help students organize and represent knowledge of a subject.
Concept maps begin with a main idea (or concept) and then branch out to show
how that main idea can be broken down into specific topics.
Benefits
of Concept Mapping
Concept mapping serves several
purposes for learners:
1) Helping
students brainstorm and generate new ideas
2) Encouraging
students to discover new concepts and the propositions that connect them
3) Allowing
students to more clearly communicate ideas, thoughts and information
4) Helping
students integrate new concepts with older concepts
5) Enabling
students to gain enhanced knowledge of any topic and evaluate the information
How
to Build a Concept Map
Concept maps are typically
hierarchical, with the subordinate concepts stemming from the main concept or
idea. This type of graphic organizer however, always allows change and new
concepts to be added. The concept positions on a map can continuously change,
while always maintaining the same relationship with the other ideas on the map.
Start with a main idea, topic, or
issue to focus on.
Find the key concepts that connect
and relate to your main idea and rank them; most general, inclusive concepts
come first, then link to smaller, more specific concepts.
Finish by connecting
concepts--creating linking phrases and words.
Once the basic links between the
concepts are created, add cross-links, which connect concepts in different
areas of the map, to further illustrate the relationships and strengthen
student’s understanding and knowledge on the topic.
Concept
Maps in Education
When created correctly and
thoroughly, concept mapping is a powerful way for students to reach high levels
of cognitive performance. As students create concept maps, they reiterate ideas
using their own words and help identify incorrect ideas and concepts; educators
are able to see what students do not understand, providing an accurate,
objective way to evaluate areas in which students do not yet grasp concepts
fully.
Concept map of
waves
Ø Mind map
Mind mapping is a visual form of
note taking that offers an overview of a topic and its complex information,
allowing students to comprehend, create new ideas and build connections.
Through the use of colors, images and words, mind mapping encourages students
to begin with a central idea and expand outward to more in-depth sub-topics.
A mind map is a diagram used to
visually organize information. It harnesses the full range of cortical (brain)
skills – word, image, number, logic, rhythm, colour and spatial awareness – in
a single, uniquely powerful manner. In so doing, it gives you the freedom to
roam the infinite expanses of your brain. The Mind Map can be applied to every
aspect of life where improved learning and clearer thinking will enhance human
performance
Buzan suggests the following
guidelines for creating mind maps:
1.Start in the center
with an image of the topic, using at least 3 colors.
2.Use images, symbols,
codes, and dimensions throughout your mind map.
3.Select key words and
print using upper or lower case letters.
4.Each word/image is
best alone and sitting on its own line.
5.The lines should be
connected, starting from the central image. The lines become thinner as they radiate out from the center.
6.Make the lines the
same length as the word/image they support.
7.Use multiple colors
throughout the mind map, for visual stimulation and also for encoding or grouping.
8.Develop your
"own personal style" of mind mapping.
9.Use emphasis and show
associations in your mind map.
10.Keep the mind map
clear by using radial hierarchy or outlines to embrace your branches.
Difference
between Concept Map and Mind Map
Mind maps differ from concept maps
in that mind maps focus on only one word or idea, whereas concept maps connect
multiple words or ideas. Also, concept maps typically have text labels on their
connecting lines/arms. Mind maps are based on radial hierarchies and tree
structures denoting relationships with a central governing concept, whereas
concept maps are based on connections between concepts in more diverse patterns.
However, either can be part of a larger personal knowledge base system.
Definition
of a Mind Map
A mind map is a visual
representation of hierarchical information that includes a central idea
surrounded by connected branches of associated topics.
Benefits
of Mind Maps
1) Help
students brainstorm and explore any idea, concept, or problem
2) Facilitate
better understanding of relationships and connections between ideas and
concepts
3) Make
it easy to communicate new ideas and thought processes
4) Allow
students to easily recall information
5) Help
students take notes and plan tasks
6) Make
it easy to organize ideas and concepts
7) A
Mind Map is a powerful graphic technique which provides a universal key to
unlock the potential of the brain
How
to Mind Map
All mind maps begin with a main
concept or idea that the rest of the map revolves around, so choosing that idea
or topic is the first step. Begin by creating an image or writing a word that
represents that first main idea.
From that main idea, create
branches (as many as needed), that each represent a single word that relates to
the main topic. It’s helpful to use different colors and images to
differentiate the branches and sub-topics.
Then, create sub-branches that stem
from the main branches to further expand on ideas and concepts. These
sub-branches will also contain words that elaborate on the topic of the branch
it stems from. This helps develop and elaborate on the overall theme of the
mind map. Including images and sketches can also be helpful in brainstorming and
creating the sub-branch topics.
Mind maps can be created on paper
but are more easily and fluidly created on a computer with mind mapping
softwares
Mind
Maps in Education and Teaching with Mind Maps
Mind mapping is a beneficial
learning tool to help students learn any topic and think creatively. Mind maps
are particularly helpful in the writing process and provide students with a
natural way of thinking and building thoughts on a story plot or theme.
Mind maps also provide teachers
with insight into their students’ thought process regarding a specific topic.
By asking students to create mind maps demonstrating their comprehension of a
concept, teachers are able to understand what a student’s prior knowledge was
and how well the student understands the assignment or the material being
taught. This is a very effective way of evaluating students’ understanding.
A Mind Map
Ø Analogies
Generally means a comparison
between one thing and another, typically for the purpose of explanation or
clarification.
An analogy is a comparison of the
similarities of two concepts. The familiar concept is called the analog and the
unfamiliar one the target. Both the analog and the target have features (also
called attributes). If the analog and the target share similar features, an
analogy can be drawn between them.
For Example : Atomic structure and
solar system.
A water-circuit
diagram and an electric-circuit diagram (Analogy)
The analogies used in
classrooms, textbooks, and web-based instruction should be designed to promote
the cognitive process of constructing relations between what is already known
and what is new.
Ø Blended learning
Blended learning refers to a
strategic and systematic approach to combining times and modes of learning,
integrating the best aspects of face-to-face and online interactions for each
discipline, using appropriate ICTs.
Blended learning can increase
access and flexibility for learners, increase level of active learning, and
achieve better student experiences and outcomes. For teaching staff, blended
learning can improve teaching and class management practices. A blend might include:
• face-to-face and online learning
activities and formats
• traditional timetabled classes
with different modes, such as weekend, intensive, external, trimester
• well established technologies
such as lecture capture, and/or with social media and emerging technologies
• simulations, group activities,
site-based learning, practicals.
Benefits
of blended learning
1.
Improves efficiency
2.
Saves money
3.
Personalizes learning
4.
Better student data/evaluation
5.
Variety of Learning Experiences.
Ø Problem-based learning (PBL)
Problem-based learning (PBL) is
an exciting alternative to traditional classroom learning.
With PBL, teacher presents with a problem, not
lectures or assignments or exercises. Since students are not handed
"content", learning becomes active in the sense that they discover
and work with content that they determine to be necessary to solve the problem.
In PBL, teacher acts as
facilitator and mentor, rather than a source of "solutions."
Problem based learning will
provide opportunities to
§ examine and try out what
learners know
§ discover what learner
need to learn
§ develop people skills
for achieving higher performance in teams
§ improve communications
skills
§ state and defend
positions with evidence and sound argument
§ become more flexible in
processing information and meeting obligations
§ Practice skills that
will need after education.
§ Helps problem solving
ability
Steps in PBL
1. Explore the issues:
Teacher introduces an "ill-structured" problem.
Discuss the problem statement and list its significant parts.
Teacher introduces an "ill-structured" problem.
Discuss the problem statement and list its significant parts.
2. List "What do we know?"
What do you know to solve the problem?
This includes both what you actually know and what strengths and capabilities each team member has.
What do you know to solve the problem?
This includes both what you actually know and what strengths and capabilities each team member has.
3. Develop, and write out, the problem statement
in your own words:
4. List out possible solutions
5. List actions to be taken with a timeline
6. List "What do we need to know?"
7. Write up your solution with its supporting documentation, and
submit it.
8. Presenting and defending your conclusions:
9. Review your performance
Ø Mnemonics
Mnemonics are devices to help us remember (aid
memoire or memory aid). They come in many varieties and can aid memorisation of
many types of information.
Mnemonics are memory devices that help learners
recall larger pieces of information, especially in the form of lists like
characteristics, steps, stages, parts, phases, etc.
Different types of Mnemonic devices
1) Method
of Loci
The method of loci is a method of memorizing
information by placing each item to be remembered at a point along an imaginary
journey. The information can then be recalled in a specific order by retracing
the same route through the imaginary journey. Loci is the plural for of the
Latin word, locus, meaning place or location.
2) The
peg-word method
In the pegword mnemonic technique, you first
memorize the short rhyme. Then, using these words as pegs, you create a visual
image of each of the words you wish to remember.
3) Rhyming
A rhyme is a repetition of similar sounds (or
the same sound) in two or more words, most often in the final syllables of
lines in poems and songs. It can be effectively used as mnemonic.
4) Initial
letter strategy
Letter strategies include acronyms and
acrostics (or sentence mnemonics). For example, the acronym VIBGYOR
5)
Acronyms : Use first letter from a group of words
6)
Acrostics: Make a sentence instead of artificial word.
Using the artificial word “ My Very Educated Mother Just Showed Us Neptune” helps to
remember 8 planets in order of distance from Sun. That is Mercury, Venus,
Earth, Mars, Jupiter, Saturn, Uranus, Neptune,.
7)
The keyword method: Use of Imagery for remembering difficult,
uncommon words items, situations.
8)
Chunking: Splitting the whole into chunks of five, two, or three
digits.
Ø Graphic organizer
A
graphic organizer is a visual and graphic representation of relationships among
ideas and concepts. This instructional tool comes in a variety of formats that
help students process information they have gathered and organize their ideas.
Graphic
organizers make teaching and learning more interesting. Visually appealing and
accessible to both struggling and advanced students, graphic organizers help students
to:
•
connect prior knowledge to new information
•
integrate language and thinking in an organized format
•
increase comprehension and retention of text
•
organize writing
•
engage in mid- to high levels of thinking
Graphic
organizers guide learners’ thinking as they fill in and build upon a visual map
or diagram. Graphic organizers are some of the most effective visual learning
strategies for students and are applied across the curriculum to enhance
learning and understanding of subject matter content. In a variety of formats
dependent upon the task, graphic organizers facilitate students’ learning by
helping them identify areas of focus within a broad topic.
In
addition to helping students organize their thinking and writing process,
graphic organizers can act as instructional tools. Teachers can use graphic
organizers to illustrate a student’s knowledge about a topic or section of text
showing areas for improvement.
What are Graphic Organizers?
“Graphic organizers are visual representation of knowledge that
structures information by arranging important aspects of a concept or topic
into a pattern using labels. Their main function is to help present information
in concise ways that highlight the organization and relationships of concepts”.
Definition of a Graphic Organizer
A graphic organizer is a visual display that demonstrates relationships
between facts, concepts or ideas. A graphic organizer guides the learner’s
thinking as they fill in and build upon a visual map or diagram. They are also
informally used as a term to describe all visual learning strategies such as
concept mapping, mind mapping, and more.
Types of Graphic Organizers
Webs, concept maps, mind maps and plots such as stack plots and Venn
diagrams are some of the types of graphic organizers used in visual learning to
enhance thinking skills and improve academic performance.
Graphic organizers are communication devices that show the organization
or structure of concepts as well as relationships between concepts. Spatial
arrangements depicting the information’s structure reduce the cognitive demands
on the learner. The learner does not have to process as much verbal information
to understand the information. This is one of the reasons why graphic organizers
are such powerful devices for students with language-based learning
disabilities.
Why use graphic organizers?
1)
Using
Graphic Organizers, students are considerably more likely to understand and
remember the content subject you are teaching.
2)
Graphics
help students separate what is important to know from what might be
interesting, but not essential information.
3)
It is a
powerful way to facilitate understanding.
4)
Students
are more likely to become strategic learners.
5)
Reading
and writing skills, communication skills, and analytical, critical, and
creative thinking skills are all subject to improve when students learn
recognize these patterns of thinking, construct, and use graphic organizers.
6)
Tools
for critical and creative thinking
7)
Tools
for organizing information
8)
Tools
for understanding information and relationships
9)
Tools
for depicting knowledge and understanding
10) Tools for self-learning
Reference
1) Mathew,T.K.
& Mollykutty (2012) Science Education-Theoretical Bases of Teaching &
Pedagogic Analysis, Chengannur: Rainbow Publications
2) Mohan,
R (1995). Innovative science teaching
for physical science. New Delhi: Prentice Hall
3) Sharma,R.C.
(1985) Modern Science Teaching. New Delhi: Dhanpat Rai & Sons.
4) Sivarajan,K &Faziluddin,A.(2005) Science
Education. Calicut University : Central
Co operative stores
5) Das,
R.C. (1985) Science teaching in schools. New Delhi: Sterling Publishers
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Mathew (2014) Teaching Science for Biological and Physical Sciences. Malappuram
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