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Asia-Pacific Forum
on Science Learning and Teaching, Volume 11, Issue 2, Article 13 (Dec., 2010) |
According to the pre-test results, there was no statistically significant difference between the CG and EG. However, the post-test results revealed that there was a statistically significant difference in favor of the EG compared to the CG in terms of the students’ achievement (p<.01). Examples of the five questions used in the post-test about matter and its states and student responses to them are given below.
The question “What are the states of matter in nature?” aimed to reveal the children’s knowledge concerning the states of matter. Matter is classified by its physical state as a solid, liquid or gas. As seen in Table II below, based on the post-test results, although all children in the EG knew the states of matter in nature, less than half of the children knew in the CG. This difference was statistically significant. However, there was one interesting finding in this question. Two children (11.8%) in the CG thought that matter can exist in four different states; solid, liquid, gas or evaporated. These children tended to consider vapor differently from the gas state of matter. They were not aware that vapor is the gaseous state of water.
Table II. Responses to the question “What are the states of matter in nature?”
The responses of the children Control Group
(pre-test)
f %Experimental
Group
(pre-test)
f %Control Group
(post-test)
f %Experimental
Group
(post-test)
f %Scientific responses*
1
5.9
2
12.5
8
47.1 16
100
Matter exists as solid, liquid or gas in nature.
(1)
5.9
(2)
12.5
(8)
47.1 (16)
100
Partially scientific responses
4
23.5
3
18.8
2
11.8 -
-
Matter can exist as evaporated, solid, liquid or gas in nature.
(4)
23.5
(3)
18.8
(2)
11.8 -
-
Non-scientific responses
11
64.7
10
62.5
7
41.1 -
-
a) Misconception
7
41.2
5
31.5
6
35.3 -
-
Matter exists only as solid.
(2)
11.8
(4)
25.0
(2)
11.8 -
-
Matter exists only as liquid.
(5)
29.4
(1)
6.3
(4)
23.5 -
-
b) Nonsensical
4
23.5
5
31.5
1
5.9 -
-
Matter exists only as meals and drinks.
(4)
23.5
(5)
31.5
(1)
5.9 -
-
No answer
1
5.9
1
6.3
-
- -
-
Total
17
100
16
100
17
100 16
100
*X2(1)= 11.64, P<.01 for post-test.
The possible reason for this view is that children often observe hot (boiling) meals, boiling water, etc. in the kitchen, and they simultaneously see rising steam into the air. These experiences may lead children to think that if air is the gaseous state of matter, this rising steam is an evaporated state of matter. Similarly, in the study conducted by Andersson (1992), students tended to regard steam as a different substance from water.
The following question, “What state of matter is a sponge?”, explores children’s ideas about the solid state of matter. A sponge is a solid state of matter. Solid is the state in which matter maintains a fixed volume and shape. Solids resemble liquids in having a definite volume, but differ from both liquids and gases in having a definite shape. A solid does not take the shape of the container, and it will not change regardless of what container it is placed in. A sponge is a solid, yet it changes its shape when it is pressed down. It has a lot of air trapped inside it (the holes) and it is the air that is compressed, causing the sponge to look smaller and change shape.
Table III. Responses to the question “What state of matter is a sponge? Explain your reason.”
The responses of the children Control Group
(pre-test)
f %Experimental
Group
(pre-test)
f %Control Group
(post-test)
f %Experimental
Group
(post-test)
f %Scientific responses*
1
5.9
1
6.3
3
17.7 16
100
It is solid because it has a certain shape.
(1)
5.9
-
-
(2)
11.8 (13)
81.3
It is solid because it does not flow like liquids.
-
-
(1)
6.3
(1)
5.9 (3)
18.8
Partially scientific responses
-
-
-
-
-
- -
-
Non-scientific responses
15
88.2
13
81.3
13
76.5 -
-
a) Misconception
15
88.2
13
81.3
13
76.5 -
-
Sponge is a soft state of matter. We feel softness when we touch it.
(6)
35.3
(7)
43.8
(5)
29.4 -
-
Sponge is a liquid state of matter because it is soft, not like a solid.
(9)
52.9
(6)
37.5
(8)
47.1 -
-
b) Nonsensical
-
-
-
-
-
- -
-
No answer
1
5.9
2
12.5
1
5.9
-
-
Total
17
100
16
100
17
100 16
100
*X2(1)= 22.88, P<.01 for post-test.
As shown in Table III, all children in the EG gave scientifically correct responses about the state of matter of a sponge. However, this decreased to 17.7 percent in the CG. A great majority of the children (76.5%) gave non-scientific responses. Of these, 29.4 percent viewed sponge as the soft state of matter. 47.1 percent said that sponge is the liquid state of matter and too soft to be solid. This finding shows that although children knew that matter exists as solid, liquid and gas, they have difficulty in applying this knowledge to the substances in their environment. They tended to classify the matter based on their feelings.
The question “What state of matter is a bag?” also revealed that the majority of children in the CG retain naive views about the state of plastic bags. They could not provide a scientific answer to this question. Children, in their daily life, often hear about petrol, plastic and bag concepts mainly through the mass media. On many occasions, it is stated that bags are made of petrol. Children might think that if petrol is a liquid, then bags should be liquid as well. In addition, 29.4 percent of children considered bags as the plastic state of the matter, based on their feelings when they touched plastic bags. Briefly, plastic bags, like the sponge, seem to form a major problem for matter classification.
Table IV. Responses to the question “What state of matter is a bag? Explain your reason.”
The responses of the children Control Group
(pre-test)
f %Experimental
Group
(pre-test)
f %Control Group
(post-test)
f %Experimental
Group
(post-test)
f %Scientific responses*
-
-
-
-
4
23.5
15
93.8
It is the state of solid. It does not flow and isn’t wet like liquids.
-
-
-
-
(4)
23.5
(15)
93.8
Partially scientific responses
-
-
-
-
-
-
-
-
Non-scientific responses
17
100
15
93.8
12
70.6
1
6.3
a) Misconception
17
100
15
93.8
12
70.6
-
-
It is the state of liquid, it contains petrol.
(7)
41.2
(5)
31.3
(6)
35.3
(1)
6.3
It is the state of plastic. We feel plastic when touching on it.
(8)
47.1
(10)
62.5
(5)
29.4
-
-
It is the state of gas it smells when burning.
(2)
11.8
-
-
(1)
5.9
-
-
b) Nonsensical
-
-
-
-
-
-
-
-
No answer
-
-
1
6.3
1
5.9
-
-
Total
17
100
16
100
17
100
16
100
*X2(1)= 16.63, P<.01 for post-test.
Solids usually have a definite shape and a definite volume. However, when a solid is broken into smaller pieces it is changed physically. For example if you crush a limestone or aspirin into a powder using wire brush or your fingers it is still a solid just in smaller pieces. Similarly, if you crush a stone into small pieces/sand it is still a solid just in smaller pieces. Nevertheless, many children (88.2%) in the CG had seriously naive views about the classification state of sand. For some, sand can pour from one cup to another just like water, hence it must be liquid. The other children tended to consider the state of sand based on its appearance. For them, sand is the dust, powder or grain state of matter.
Table V. Responses to the question “What state of matter is sand? Explain your reason.”
The responses of the children Control Group
(pre-test)
f %Experimental
Group
(pre-test)
f %Control Group
(post-test)
f %Experimental
Group
(post-test)
f %Scientific responses*
-
-
1
6.3
2
11.8
16
100
It is the state of solid. It has a certain shape.
-
-
-
-
-
-
(3)
18.8
It is solid. It is not wet when touched.
-
-
(1)
6.3
(2)
11.8
(13)
81.3
Partially scientific responses
-
-
-
-
-
-
-
-
Non-scientific responses
17
100
15
93.8
15
88.2
-
-
a) Misconception
17
100
15
93.8
15
88.2
It is liquid because it pours (pourable).
(5)
29.4
(7)
43.8
(4)
23.5
-
-
It is the state of dust (powder).
(6)
35.3
(4)
25.0
(5)
29.4
-
-
It is the state of grain.
(6)
35.3
(4)
25.0
(6)
35.3
b) Nonsensical
-
-
No answer
-
-
-
-
-
-
-
-
Total
17
100
16
100
17
100
16
100
*X2(1)= 25.88, P<.01 for post-test.
Children are not aware that granular materials like sand, wheat and flour are powders. Powders can be poured from one vessel to another, and take the shape of the vessel. In this sense, they seem to behave like fluids. However, if you pour a powder on a flat surface, they form a conical pile. If powders were fluid, they would not have piled up (Dhar, 2009).
Table VI. Responses to the question “Do you think that a tomato is matter? Explain your reason.”
The responses of the children Control Group
(pre-test)
f %Experimental
Group
(pre-test)
f %Control Group
(post-test)
f %Experimental
Group
(post-test)
f %Scientific responses*
-
-
-
-
1
5.8
14
87.5
The tomato is matter because it has mass and volume.
-
-
-
-
(1)
5.8
-
-
The tomato is a solid matter. We can find its mass and volume.
-
-
-
-
-
-
(14)
87.5
Partially scientific responses
2
11.8
4
25.0
3
17.7
2
12.5
It is matter because it is liquid inside when we eat it.
-
-
-
-
(1)
5.9
-
-
It is matter, including liquid inside and solid outside.
(2)
11.8
(4)
25.0
(2)
11.8
(2)
12.5
Non-scientific responses
15
88.2
12
75.0
13
76.5
-
-
a) Misconception
12
70.6
10
62.5
11
64.7
-
-
It is not matter, it is a vegetable.
(6)
35.3
(7)
43.8
(6)
35.3
-
-
It is matter because we eat it.
(4)
23.5
(2)
12.5
(3)
17.7
-
-
It is matter it provides us with nutrition.
(2)
11.8
(1)
6.3
(2)
11.8
-
-
b) Nonsensical
3
17.7
2
12.5
2
11.8
-
-
It is not matter because we eat it.
(3)
17.7
(2)
12.5
(2)
11.8
-
-
No answer
-
-
-
-
-
-
-
-
Total
17
100
16
100
17
100
16
100
*X2(1)= 22.14, P<.01 for post-test.
As seen from Table VI above, the question about whether a tomato is matter revealed a deep lack of understanding in relation to matter. Matter is anything that has mass and takes up space. However, only one child in the CG and 87.5 percent in the EG provided scientifically correct responses by mentioning the volume and mass of tomato. A great majority of children in the CG gave non-scientific responses. Of these, some thought that a tomato is matter because of the fact that we eat it or because it provides us with nutrition. On the contrary, two children stated that foods like tomatoes are not matter because they are eaten. Interestingly, some students (35.3%) in the CG stated that tomato is not matter because it is vegetable. This means that for some students vegetables are not matter. It is worth noting that children also need to know that a tomato is not a vegetable but a fruit.
