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Teaching and learning of classification in Life Science can be very wearisome and
dull if taught in the conventional way, using
Greek and Latin terms that are found easily
in the textbooks. Although there is a general
outcry against classification, there is a need
to put things in their place and to be
organized. Classification and its basis cannot
be avoided by those learning Life
Science. This paper looks at how this
can be taught effectively, less painfully
and in fact interestingly in the Junior
and Middle Schools, so that when
children enter High School and hear
the terms, they will carry more
meaning.
The basis of any classification system is
to group organisms according to external or internal structures, or according to basic phsiological functions. In our project we have opted for the former. We use our
school campus, one of the bestlaboratories
with varied ecosystems.
Children in fourth and fifth grades are
encouraged to explore the campus with a
smooth plate, a bangle, a hand lens and
a field notebook with a pencil.
In groups offour or five they choose a
particular area in the campus. If they
happen to see an ant or a spider in that
area, they allow the animal to crawl on
to their smooth plate.
Then they place the bangle around the
animal and prevent it from escaping for a
while. With the help of
their hand lens, they observe and record the answers pertaining to the work
sheet given.
a) Where did you find this specimen?
b) What is its colour?
c) What is its size?
d) Draw the specimen and label all the
parts you know.
e) Leave the specimen in the same place
you collected it from.
A note to the teacher here: There is no
need for excessive caution - if children feel
hesitant about any particular specimen, they
need not touch it. On the other hand it is not
advisable to tell them to be over cautious,
for children left alone are careful. Also,
animals have a special way of responding to
them.
Such a study can go on once a week for
the whole year. At the end of every term
children can talk about their collection or
illustrate them on the blackboard.
In the sixth and seventh grades, the
same observation could be taken with a
slightly different objective, i.e., to see the
common features that would help children
to deduce patterns from their field work. To
be a little more focused, children could look
at specific external features like number of
legs or number of wings if they are animals.
If plants, the kind ofleaf arrangement or the
shape of the leaf etc. The teacher has an
important task for she has to keep track of
their collections, so that she can choose
suitable and commonly seen features.
Children could label their specimens as
A, B, C, D and so on.
At the end of every term the teacher
can sum up their observations as follows. Through such tabular columns
children see how features observed in their
own specimens mayor may not be present
in other specimens.
ANIMALS
| FEATURES |
A |
B |
C |
D |
| Feelers |
|
X |
|
X |
| 2 pairs of legs |
|
X |
|
|
| 3 pairs of legs |
X |
|
|
|
| Wings |
|
|
X |
|
PLANTS
| FEATURES |
A |
B |
C |
D |
| Big Broad Leaf |
|
X |
|
|
| Small Leaflets |
|
|
X |
|
| Flowers present |
|
X |
|
|
| Fruit seen |
|
|
X |
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The next step is to begin classifying. If
movement is the important criterion for
classifying, on the basis of the tabular
column, we can classify the creatures as
The letters which represent the specimens could be placed between the brackets.
Similar patterns could be evolved for
plant observation based on the information.
This study in grades 6 and 7 enables them to
move &om a general area of study towards
details and specific patterns.
In grades 8 and 9 children study specific
habitats such as tree, bush, grass etc. along
with their collection. They spend longer
hours, especially in the morning, around a
particular habitat. They make a note of other
fauna and flora in and around the chosen
habitat. Names of some of the visitors to these
habitats are also noted down. The students
deduce the relationship between these
creatures and the habitat. This very naturally
leads to the study of a live food chain, which
the child constructs. This learning is very
different &om learning a standard food chain
drawn in their text.
For example, Under the Banyan Tree:
The fluidity is brought out by this
because the temporary dynamic aspect of
the food chain is seen and it leaves a longer
impression that results in very real learning.
The many food chains that they observe with
changes in seasons results in the formation
of a natural food web for that particular
habitat. Learning is therefore both deepened
and widened with time.
The importance of every habitat with
innumerable dependent and interdependent
organisms must be given a special place; and
how not to disturb them is the kind of question
the teacher and the pupils can keep asking.
At the end of grade 8 or at the beginning
of grade 9, introduction of the Greek and
Latin terms could be done by picking terms
that have meaning. For example, the insects
and bugs that the children have observed
could be brought under the title Arthropoda
(Arthro means jointed while Poda means foot).
More such external features of living organisms can be grouped under the standard
classification system that has been universally
accepted.
Some other such examples are:
Amphibians - Amphi means two, bio means
life - organisms that can live both on land
and in water - e.g. Frog.
Coelentrata - Animals that have a cavity in
their body as in Hydra - Microscopic
observation of pond water.
Angiosperm - Flower bearing plants like
Mango, Tamarind etc.
Such a project on live observation in
and around their classroom seeks to address
several potential skills in the children:
spotting live specimens, recording and
drawing a labelled diagram of the external
features, deducing their relationship to their
habitat, and only then locating their place in
Taxonomy.
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