Children's Misconceptions about Electricity

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					                            Children’s Misconceptions about Electricity



ABSTRACT         The effectiveness of hands-on experience in correcting the misconceptions fourth

graders have about electricity was studied. To pinpoint these misconceptions a pre-test was

administered. A search of the literature was done to find misconceptions previously studied, such

as “the belief that Ben Franklin’s kite was struck by lightning” and “static electricity is only

caused by friction.” The students had not studied any electricity concepts in their classroom

before the pre test was given. An electricity activity day was conducted to teach and correct the

misconceptions that were found through the pre-test. The students participated in additional

activities in their classroom to learn more about electricity. After the activity day, the students

were then given a post test. The results support the overall prediction that hands-on activities

can help correct students’ misconceptions about electricity. The t-value was 5.56 compared to

the t-critical on- tail value of 1.75. This shows a statistically significant increase in the number

correct from the pre-test (7.88) to the post -test (11.6).



Course: Science Theme House (Capstone)

Semester/Year: FA/2001

Instructor: Dave Barkan and Ron Hitchcock
Introduction

        “Many bright and educated adults feel inadequate about their understanding of science

phenomena. As a result, they have given up trying to make sense of even the most fundamental

concepts that are taught in elementary science classrooms. Science content is not the only

problem, however, because many adults also accepted long ago that they do not understand

science itself. For a large number of adults, science concepts and the world described by special

words, formulas, theories, and generalizations remain foreign and unapproachable. Teachers, as

a group, are no exception to this sense of inadequacy and frustration” (Steppans, 2). Students

come into classrooms with several misconceptions about scientific concepts. False information

in textbooks and teachers’ weaknesses about scientific knowledge reenforce these

misconceptions as well as foster others. Some children mature without correcting the

misconceptions and consequently pass them on to younger generations. This cycle of passing on

of incorrect information leads to the situation that students do not know the correct information

about electricity.

        Some of the misconceptions that we have found, based on our research and pre tests, are

as follows:

        1) Static electricity is caused by friction. Students believe this is true because of many

examples that are used to teach static electricity. For example, many static electricity activities

include rubbing a balloon on hair or rubbing stocking feet on a carpet. This reinforces the

misconceptio n that static electricity is caused by friction. However, this is not true. All that is

required for static electricity to occur is touching. When two objects touch, some electrons may

be transferred to one or the other surface. The result of this touc hing causes these two surfaces




                                                  2
to become oppositely charged, attracting the two surfaces. This phenomenon is known as static

electricity (Beaty, 3).

        2) Ben Franklin’s kite was struck by lightning. Many children, as well as adults,

believe that Ben Franklin’s kite was struck by lightning, therefore proving that lightning is

electrical. If lightning would have struck his kite, the electrical currents going through the kite

would have been more than enough to kill him as well as any other person nearby. The

experiment that Ben Franklin really conducted was to take a kite, with a key tied to the end,

outside during the early part of a storm. The kite string conducted electricity to the key, where

little sparks could be taken from the key, suggesting that storm clouds carry electrical particles

(Beaty, 8)

        3) Lightning moves only from sky to ground. Lightning can move in many different

directions. Not only does it go from the clouds to the ground, but it can also move from cloud to

cloud, inside one cloud, from a cloud to the air, and from the ground to the clouds.

        4) Static and current electricity are two “types” of electricity. This statement is false

because “static and current are two ways in which electrical charges can behave” (Beaty, 7).

When positive and negative charges are pushed apart while flowing through a wire, this wire

may become electrostatically charged. However, this does not mean that the charges are static.

“Charges can flow, and opposite charges can be forced to separate, but this doesn’t mean that the

two KINDS of charge are “flowing electricity” and “separated electricity.” Separation and flow

are two electrical behaviors, they are not two “kinds of electricity”(Beaty, 8).




                                                  3
Materials and Methods

       There are many references in the literature about students’ misconceptions of science.

After a search of the literature to find common misconceptions about electricity a pre- and post-

test were constructed. Before the children started their electricity unit in school, the pre test was

administered. These tests were corrected to gather initial data. The electricity unit was then

started in the classroom. During class time the teacher taught the students about atoms and their

components (protons, neutrons and electrons). A college professor was brought in to elaborate

on this concept. The teacher also did an activity in the classroom about complete electrical

circuits. One portion of this activity required the students to test many different circuits to see if

they worked. If the circuits did not work they had to state why and suggest a way to “fix” it.

       Two weeks later the electricity activity day was conducted. Four activities were set up

through which each group of ten students rotated through. Each activity was done in a separate

room. The four activities were Static Strokes, Lightning, Conductor or Insulator, and Make a

Switch. They are described in detail below.

       1) Static Strokes

        Each student was given a plastic bag with nine objects in it. The objects were paper

       clips, small pieces of Styrofoam, small pieces of aluminum foil, cotton thread, salt,

       staples, sequins, tissue paper, and Kleenex. They were also given a piece of plastic wrap

       and a paper towel. The directions were then administered to students. The students were

       to make predictions as to what would happen when the charged plastic wrap was held

       above the objects. After recording the predictions, the students were told to charge the

       plastic wrap by rubbing it with a paper towel. Then the students were to lift the plastic

       wrap and slowly lower it until it was six to ten centimeters above the object. Students

       were to do each object separately and write down observations about what happened to




                                                  4
the objects. After the students completed this, the leader explained why some objects

were attracted to the plastic wrap and why some were not.

2) Lightning

The students were given a packet called “Lightning.” The leader of the activity read

through the packet with the fourth graders following along. After reading through the

packet, the leader discussed Ben Franklin and his kite. The leader tried to correct the

misconception that Ben Franklin’s kite was struck by lightning. The children were given

a lightning sequencing activity page, which had five diagrams that led up to a lightning

strike. The children were to cut out the diagrams and arrange them in order using the

information from the lightning packet. The leader of the group inspected each child’s

sequence before the students glued the diagrams onto a lightning poster. The students

then numbered the diagrams on their lightning poster with chalk. After the posters were

completed, there was a discussion on each step in the sequence. Questions were

answered and the leader summarized the sequence leading up to a lightning strike.

3) Conductor or Insulator

The students were given a conductor/insulator worksheet and a bag full of materials. The

materials included one 15-25 centimeter wire with the ends stripped, one D battery, one

flashlight bulb, tape, and various objects to be tested. The objects consisted of a paper

clip, tape, a pencil, string, a ruler, aluminum foil, a cotton ball, and staples. The group

leader explained the activity to the students. They were to put each object in between the

light bulb and the battery to see if it was a conductor or an insulator. However, before

they tested each object, they were to make predictions about what they thought each

object would do. After making predictions, they were instructed to test each object and

write down the observations.

4) Make a Switch

Each student was given a handout explaining how to make a switch. Before beginning

the activity, the group leader discussed the activity directions. The students were also



                                          5
       given a bag with all of the materials. The bags included a D battery, three pieces of wire

       with the ends stripped, two brass paper fasteners, a light bulb (1.5 volt), one paper clip,

       masking tape, and an 8x8 centimeter piece of tagboard. The students were the n

       instructed to make the switch as it appeared on their handout. The group leader allowed

       the students to work on the switch independently for approximately five minutes. After

       this, the students who made the switch work were allowed to help the others who could

       not construct the switch properly. When all of the students’ switches worked, the group

       leader discussed any questions the students had pertaining to why some switches did not

       light the bulb while others did.



       The post tests were administered on the day following the electricity activity day. The

tests were corrected to determine the results which are reported below.

       To insure anonymity, but still be able to compare the pre- and post-test results of each

student, a numbering/lettering system was devised. The fourth grade teacher assigned each child

a number which was written on his or her test. The students took the tests, which were later

collected and given to the advisor by the fourth grade teacher. The advisor then randomly

converted these numbers into letters, to keep the anonymity secure.

Results

       The following equations were used to calculate our t-test results:
               µ1 = µ 2                                          s1 s 2
                                                   σx1 − x 2 =      +
               µ1 − µ 2 = 0                                      µ1 µ 2


       Null Hypothesis:
                                              µ 1 = 16
                                              µ 2 = 16
           x1 − x 2
                                              x1 = 7.875
       t= σx1 − x 2
                                              x 2 = 11.5625
                                              s1 = 3.3166
                                              s 2 = 3.8625



                                                 6
These numerical values were used in the equations to compute our results for each separate

students’ responses on the entire test. These are shown in the following two tables:
Table 1.1
 Student Pretest Post-
                      Test
           Correct Correct

    B         6        14      t-Test: Paired Two-Sample
                                        for Means
    C         7        12
    E         5        12                Mean                7.88                      11.6
    F         9        11               Variance             3.32                      3.86
    G         9        11             Observations           16                          16
    H        10        13          Pearson Correlation       0.021
    I         8         9           Pooled Variance          3.59
    J         5        11          Hypothesized Mean         0
                                       Difference
   K          6         9                  df                15
   L         10         8                   t                5.56
   M          8         9
   N          8        14           t Critical one-tail      1.75
   O          5        13
   P         10        14
   R          8        14
   S         10        12
   T          8        13
   D         10        n/a
   Q            7      n/a




                                                7
        The results showed that following the activity day, the fourth graders’ post-test scores

improved as compared to the students’ pre-test scores. These results showed that learning in the

classroom and doing hands-on activities, as well as discussing the misconceptions, helped the

fourth graders understand electricity much better. The mean value showed that less than half of

the questions were answered correctly on the pre-test, but over half of the questions were

answered correctly on the post-test. The t- value (t = 5.56) is greater than the t critical one-tail

(1.75) showing that there was a statistically significant improvement for each student’s result on

the pre- and post-tests.

        Question number seventeen was separated from the rest of the test because it was a

complex question and required separate analysis (pictured below). This question tested students’

knowledge concerning closed and open circuits. There were diagrams of five correct

connections and seven incorrect connections. To get full credit for the question, students were

asked to circle the circuits that would work and to not circle the ones that would not work. Even

though the mean value does not show a large improvement from the pre-test to the post-test

results, the improvement was shown to be statistically significant , t = 3.29 > t critical one-tail =

1.69.

17) Circle the following connections that will light the bulb.




                                                  8
Table 1.2
                                    Question 17


Student Pretest      Post-
                     Test
            Correct Correct

   B          4        9         t-Test Two Sample
                              Assuming Equal Variance
   C          8       10
   E          7        8              Mean              7.25   9.19
   F          7        8            Variance            3.8    1.76
   G          9       10          Observations          16       16
   H          9        8         Pooled Variance        2.78
   I          5       11        Hypothesized Mean       0
                                   Difference
   J           5       9               df               30
   K           5      11                t               3.29
   L           6      10
   M           8       9          t Critical one-tail   1.70
   N           9       9
   O           9      11
   P           8       6
   R           8       9
   S          10       9
   T           3       9
   D           5      n/a
   Q           8      n/a




                                              9
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    Q       u       e       s       t       i       o       n   #   1   7




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                                                                            10
The following equations and numeric values were used to find the percent variance on each
separate question:

              P1-P2=0



                               P1(1 − P 2)   P 2(1 − P 2)
                σp1 − p 2 =
− =
1 0
P2
                                   n1             n2




                      Null Hypothesis

                            P1 − P 2
                      t=
                           σP1 − P 2


                      n1 = 17
                      n 2 = 17
                      P1 = .52
−
σ
=
n
p
1
2   +
    n
    2
    1
                      P2 = .50




=
σ
t   −
    P
    2
    1




                                  ,

=
2
P
.
5
1   =
    .
    p
    5
    0
    ,
    2




                                                  11
       When the t- value is greater than the null t-value it shows that there was a statistically

significant change in the test results. On seven out of the sixteen questions the t-value was

greater than the null t-value.

Individual Question Analysis

       Any t-values that are greater than the null t-values show a statistically significant

improvement. The post-test percentage may show an improvement from the pre-test, however

this improvement is not statistically significant unless the t-values are greater than the null t-

values(refer to table 1.3). Below is an exact copy of the test questions. An analysis of each

question follows. The correct answers are circled.




1) All matter is made up of atoms.

       True           False

       The students received a pre-test average of 41.2% correct. The post-test percentage was

       76.5. The students improved from the pre-test to the post-test because of the materials

       that were presented to them in class about atoms. This was a statistically significant

       change which was shown by the t- value of 2.24 which is greater than the null- t value of

       2.12.

2) Electrons have what kind of charge?

       a) positive charge

       b) no charge

       c) negative charge

       The students received a pre-test average of 41.2% correct. The post-test average was a

       100% correct. The students also learned this information in a classroom activity about

       atoms and their components. The t- value was 4.93 compared to the null-t value which

       was 2.12. These values are not only statistically significant, but also show that a

       misconception was corrected in the minds of the fourth graders.



                                                 12
3) What particles are located in the nucleus of an atom?

       a) protons and neutrons                   b) protons and electrons

       c) only neutrons                          d) only electrons

       The students received a pre-test average of 35.3% correct. The post-test average was a

       70.6% correct. This information was taught to the students in the same activity about the

       atom and its components. The t-value was 2.20 compared to the null- t value which was

       2.12. The difference between the two values was statistically significant.

4) Static electricity is caused only by friction.

       True            False

       The students received a pre-test average of 47.1% correct. The post-test average was a

       17.6% correct. The activity done with the students about static electricity may have

       added to their misconceptions that static electricity is only caused by friction. The

       activity done had the students rub the plastic wrap with a paper towel, thus the students

       might have concluded that friction was the only cause of static electricity. The t- value

       was 1.94 which was considerably less than the null t- value of 2.12.

5) Which of the following is true?

       a) there are no types of electricity

       b) static electricity is a type of electricity

       c) there are three types of electricity

       d) current and static electricity are the only types of electricity

       The students received a pre-test average of 11.8% correct. The post-test average was a

       0% correct. This misconception was not corrected, but added to and continued. The

       teachers may have taught the children false concepts about the different “kinds” of

       electricity. This assumption is based on the fact that the students were not able to answer

       this question at all on the post-test. The t-value was 1.51 which was not statistically

       significant, therefore the null hypothesis was supported.




                                                    13
6) Ben Franklin’s kite was struck by lightning proving that lightning is electrical.

       True             False

       The students received a pre-test average 5.9% correct. The post-test average was 100%

       correct. This misconception was corrected through the lightning activity done during the

       electricity activity day. The t- value was 16.47 which shows an excellent statistical

       improvement over the null t-value of 2.12.

7) A material which allows electricity to pass through it is a(n):

       a) electromagnet

       b) conductor

       c) insulator

       The students received a pre-test average of 35.3% correct. The post-test average was

       82.4% correct. An activity was done about conductors and insulators during the

       electricity activity day. This activity helped correct some of the students’

       misconceptions. The t-value was 3.18 which shows a statistically significant

       improvement.

8) Lightning only moves from sky to ground.

       True             False

       The students received a pre-test average of 70.6% correct. The post-test average was

       94.1%. The students learned about this concept during the electricity activity day.

       Although a few students’ misconceptions were corrected, it was not a statistically

       significant change because the t-value was 1.89. The high average pre-test score and

       small sample size make it difficult to show statistical improvement here.



9) An example of an insulator is:

       a) copper wire

       b) rubber

       c) iron



                                                14
       The students received a pre-test average of 35.3% correct. The post-test average was

       64.7% correct. The students participated in an activity about conductors and insulators

       during the electricity activity day. The students were given rubber to test whether it was

       a conductor or insulator. The fact that rubber is an insulator needs to be stressed to them

       again so the misconception can be thoroughly corrected. Although the post-test showed

       an improvement compared to the pre-test, this improvement was not statistically

       significant because the t- value was 1.79.

10) A neutral object has the same number of protons and electrons.

       True               False

       The students received a pre-test average of 47.1% correct. The post-test average was

       52.9% correct. This concept was briefly touched upon during a classroom activity on

       atoms. However, it was not enough information for the students’ misconceptions to be

       corrected. The t-value was .339 which was not statistically significant.

11) Friction can be caused by rubbing two objects together.

       True               False

       The students received a pre-test average of 88.2% correct. The post-test average was

       88.2% correct. This misconception was discussed during the static electricity activity on

       the electricity activity day. Even though there was no change from the pre-test to the

       post-test, one positive point is no new misconceptions about this subject were fostered.

12) An insulator is any item that does not allow electricity to flow easily through it.

       True               False

       The students received a pre-test average of 41.2% correct. The post-test average was

       82.4%. The students learned about this concept during the electricity activity day. This

       improvement was statistically significant based on the fact that the t-value was 2.73.

13) An example of a conductor is:

       a) a cotton ball

       b) aluminum



                                                15
       c) paper

       The students received a pre-test average 94.1% correct. This means that one student got

       this question wrong each time. The post-test average was 94.1% correct. An activity

       was done about conductors and insulators during the electricity activity day.

14) Electrons are located where in the atom?

       a) in the nucleus

       b) atoms don’t have electrons

       c) orbiting (circling) the nucleus

       The students received a pre-test average of 47.1% correct. The post-test average was

       94.1 % correct. This concept was taught in the classroom during the activity on atoms.

       Most of the students’ misconceptions were corrected about the components of an atom.

       There was statistically significant improvement based on the t-value of 3.51.

15) What is at the center of every atom?

       a) a nucleus

       b) an electron cloud

       c) an open circuit

       The students received a pre-test average of 52.9% correct. The post-test average was

       70.5 % correct. Again the students learned about this during the classroom activity on

       atoms. Even though some students’ misconceptions about this concept were corrected,

       the information may have been presented in too difficult a manner for them to

       comprehend. Although the post-test shows an improvement over the pre-test it was not

       statistically significant given the small sample size and based on the t-value of 1.07.

16) Opposite charges attract.

       True           False

       The students received a pre-test average of 58.8% correct. The post-test average was

       82.4% correct. This topic was touched upon during the static electricity activity done

       during the electricity activity day. This misconception was not corrected for everyone,



                                               16
                             Pretest  Post-test
                     QUESTION Average Average
                     NUMBER     Correct   Correct      FP1-P2     t     Null t
                                   %        %
       however           1       41.2      76.5         0.158    2.24   2.12     many students
                         2       41.2      100          0.119    4.93   2.12
       did learn         3       35.3      70.6         0.160    2.20   2.12     enough
                         4       47.1      17.6         0.152    1.94   2.12
                                                                                 information to
                         5       11.8       0          0.0782    1.51   2.12
       correct it.       6        5.9      100         0.0571    16.5   2.12     This concept
                         7       35.3      82.4         0.148    3.18   2.12
       could             8       70.6      94.1         0.124    1.89   2.12     have been
                         9       35.3      64.7         0.164    1.79   2.12
       discussed        10       47.1      52.9         0.171   0.339   2.12     more thoroughly
                        11       88.2      88.2         0.111      0    2.12
       during                                                                    the static
                        12       41.2      82.4         0.151    2.73   2.12
                        13       94.1      94.1        0.0808      0    2.12     electricity
                        14       47.1      94.1         0.134    3.51   2.12
       activity         15       52.9      70.5         0.164    1.07   2.12     which may have
                        16       58.8      82.4         0.151    1.56   2.12
       helped                                                                    more students

       correct this misconception. There was no statistically significant improvement based on

       a low t-value of 1.56.




Table 1.3




                                                  17
Conclusion

       The prediction that misconceptions about electricity can be corrected was supported by

the data. Based on the results in Table 1.1, there was an overall statistically significant

improvement in the individua l test scores. Although only two misconceptions were completely

corrected, the learning activity along with classroom instruction helped correct many of the

misconceptions that the students had (Table 1.3). There were only two misconceptions where

the students did not improve on the post-test scores in comparison with the pre-test scores.

These were the misconceptions stated in questions number four and five. These misconceptions

may not have been thoroughly discussed in class. Students may have also received additional

misinformation during the activities as this was not controlled or observed. Another theory

concerning the lack of improvement from the pre-test to the post-test was the structure and

wording of these two questions. In order to fully correct all of the misconceptions that were

found by the pre-test, further activities and correct instruction need to be implemented in the

students’ curriculum.




                                            References

Abruscato, Joseph. 2000. Teaching Children Science: A Discovery Approach. Alllyn and

       Bacona, Boston: pgs 204, 421-422.

Beaty, William J. (2001, Oct.) “Electricity” Misconceptions in K-6 Textbooks. [On-Line].

http://www.eskimo.com/~billb/miscon/eleca/html#exist.



                                                 18
Beaty, William J. (2001, Oct) “Static Electricity” Misconceptions. [On- Line].

       http://amasci.com/emotor/stmisco.html#one.

Stepans, Joseph. 1996. Targeting Students’ Science Misconceptions: Physical Science Concepts

       Using the Conceptual Change Model. Idea Factory Inc, Florida: pgs 1-7.




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