Teaching Nanotecnologia..

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Copyright 2011 American Scientific PublishersAll rights reservedPrinted in the United States of America

Journal ofNano Education

Vol. 3, 5161, 2011

Teaching Nanotechnology Using Student-Centered

Pedagogy for Increasing Students

Continuing Motivation

Ron Blonder and Merav Dinur

Department of Science Teaching, The Weizmann Institute of Science, Rehovot 76100, Israel

This paper presents a nanotechnology module that was designed for high-school students. A unique

way to adapt advanced contents to high-school students level was applied by using constructivist

pedagogy in which the students are at the center of the learning. Moving from teacher-centered

to student-centered pedagogy switches the control of the learning environment from the teacher tothe learners. Students interviews and a semantic differential (SD) questionnaire were used to learn

about students motivation and their perceptions. The study shows that students appreciated the

topic of LED and found that it increased their motivation to further learn about LED, nanotechnology,

and chemistry. The student-centered pedagogy that was chosen also contributed to a positive effect

regarding students continuing motivation.

Keywords: Nanotechnology, LED, Student-Centered, Continuing Motivation, Enrollment inChemistry, High School.

1. INTRODUCTION

1.1. Theoretical Background

Many European countries have been experiencing signifi-

cant problems when trying to encourage students to pur-sue advanced studies in chemistry (Osborne and Dillon,

2008). This finding is a reason for significant concernsfor both science educators as well as for decision makers.

Throughout Europe (Jenkins and Pell, 2006), the numberof students who have chosen to study science, technol-

ogy, engineering and mathematics subjects has dramati-cally decreased. In the US, students that choose to major inscience and engineering have been found to be at a lower

level and quality over the years (Lowell et al., 2009).

The ROSE study (Jenkins and Pell, 2006), whichfocused on students attitudes toward science, was con-ducted in more than 20 countries, both developed and

underdeveloped. This study showed that in general, stu-dents expressed negative attitudes toward school science in

countries whose economic conditions were more advanced(compared with underdeveloped countries). A negative

correlation was found between students responses and theUN Index of Human Development (Sjberg and Schreiner,

2005). For example, the more advanced a country is, the

Author to whom correspondence should be addressed.

less its young people are interested in studying science.Likewise, an analysis of the data from the Third Inter-

national Mathematics and Science Study (TIMSS), con-ducted in 1999, measuring both students attainment andstudents attitudes toward science, revealed that the higherthe average students achievement, the less positive aretheir attitudes toward science and their interest in science(Mullis et al., 1999). In a later TIMSS study conducted in2007, in many countries (including Israel) students atti-tudes toward science decreased (Martin et al., 2008). Inthe US, however, the situation was found to be different.Lowell et al., (2009) stressed that the Science, Technology,Engineering, and Mathematics (STEM) retention along theeducational system shows strong and even increasing rates

of retention from the 1970s to the late 1990s. The overalltrend of increasingly strong STEM retention rates, how-ever, was accompanied by simultaneous and sometimessharp declines in retention among the highest performingstudents (in the 1990s). In other words, young people donot choose the science and engineering fields not becauseof lack of their ability, but because of other factors, forexample, they do not find those jobs attractive.

In view of these worrisome survey results, science edu-cators began to search for ways to make chemistry a moreappealing subject to students. We suggest two complemen-tary directions that could be taken to improve students

motivation to study chemistry:J. Nano Educ. 2011, Vol. 3, No. 1/2 1936-7449/2011/3/051/011 doi:10.1166/jne.2011.1016 51


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Teaching Nanotechnology Using Student-Centered Pedagogy for Increasing Students Continuing Motivation Blonder and Dinur

(1) reconsidering the chemistry contents that are learnedin high-school chemistry, and(2) rethinking the teaching pedagogy.

Continuing motivation was defined by Maehr (1976) asthe tendency to return to and continue working on tasksaway from the instructional contexts in which they were

initially introduced (p. 443). Continuing motivation forscience learning is expressed by reengaging in science-related extracurricular activities that do not result fromsome external pressure or requirement, such as watch-ing science-related TV programs, browsing science-relatedwebsites, going to science museums, doing hands-on activ-ities at home or with friends, and looking at the sciencesection in newspapers. This can also be connected to theextent to which students enroll in science after complet-ing basic science courses (Hofstein et al., 1977; Shernoffand Hoogstra, 2001). Despite its importance, surprisinglylittle research has focused on continuing motivation asan important educational outcome (Vedder-Weiss and For-tus, 2011). An exception is the work of Pascarella et al.(Pascarella et al., 1981), who examined some classroomenvironment correlates of continuing motivation in sci-ence for school students. Their findings indicate that theextent to which teachers, rather than students, controlledthe learning environment was positively correlated to stu-dents achievements in science but was negatively associ-ated with continuing motivation. Supporting evidence forPascarellas claim was described in the work of Vadder-Weiss and Fortus (2011), who found a positive correlationbetween the school culture and the development of adoles-cents motivation for science learning in school and out of

school. Another factor that was found to positively affectcontinuing motivation is the utility of science content andscience lessons (Pascarella et al., 1981).

The advance of science, which is continuously taking

place, includes attractive topics that have the potential tocapture the interest of young people. Science educatorshave tried to apply this potential in a variety of programsthat were developed to bridge the gap between moderndevelopments in science and currently taught high-schoolscience programs. Outreach programs in different scien-tific areas were developed for that purpose. The subjectof nanotechnology has the potential to be appealing for

high-school students as a modern research subject that hasmany potential technological applications. Trying to intro-duce nanotechnology in high school resulted in severaleducational programs, curricula, and modules in the areaof nanotechnology. For examples, see (Alford et al., 2009;Avila et al., 2010; Crone, 2010; Greenberg, 2009; Harmerand Columba, 2010; Hingant and Albe, 2010).

Walters and Bullen (2008) developed a one-week inter-session course on nanomaterials aimed at introducing stu-dents to nanomaterials by explaining their synthesis and bycharacterizing them. In addition, the course enhanced stu-dents understanding of the potential implications of nano-

materials to society. Harmer and Columba (2010) explored

factors that contributed to engaging middle-school stu-

dents during a problem-based inquiry, which introducednanoscale science and discussed nanotechnology-based

solutions. This approach proved highly engaging and ledto students having a better understanding of nanoscale sci-

ence, nanotechnology, and electron microscopy. In a differ-

ent program, a two-day workshop was designed to expose11th and 12th grade students to industrial applications

of Materials Science and Nanotechnology (Avila et al.,2010). During the course the students teams were given

problem-based learning exercises based on the mechanical

and thermal properties of a variety of polymeric materialsand candy. Most of the students claimed to have solidified

their knowledge of materials performance, in addition to

learning budgeting and how to trade off. A comprehensivecourse introduction to materials and nanotechnology was

conducted for chemistry high-school teachers (Blonder,2011). This course was designed to make the teachers

nanoliterate, and included lectures and demonstrations of

characterization methods used in nanotechnology. In a dif-ferent work (Ambrogi et al., 2008), high-school students

learned about nanotechnology and prepared a Power Pointpresentation to introduce nanochemistry and nanotechnol-

ogy to younger students. Sweeney (2006) developed a

nanotechnology ethics seminar series that included ananalysis of students and participating research facultys

perspectives concerning social and ethical issues associ-

ated with nanotechnology research.Different pedagogical approaches were taken in the dif-

ferent programs; they varied from courses that focusedon nanotechnology content and methods (Blonder, 2011),

through lab courses (Brazell et al., 2009; Harmer and

Columba, 2010; Samet, 2009; Walters and Bullen, 2008),and even teaching nanotechnology using the ethics per-

spective via socio-scientific issues (Sweeney, 2006).

1.1.1. Pedagogy

Although advanced and modern scientific contents and

their technological applications are appealing and have the

potential to positively influence and motivate students toenroll in science courses, they are absent from most high-

school curricula, mainly because of the hierarchical natureof science (Kapon et al., 2009). If we wish to incorporatecontemporary science contents, such as nanotechnology,

into high-school science lessons, we must think of a teach-ing pedagogy that can bridge the gap between the students

pre-knowledge and the advanced content.

It was suggested that simple teaching models wouldassist high-school teachers in bridging the gap between

student knowledge and modern instrumentation. A simpleteaching model for an X-ray detection method was sug-

gested (Peralta et al., 2008) to demonstrate how the X-ray

technique uses film for X-ray detection. Santos, Luiz, and

de Carvalho (2009) presented a simple model for teaching52 J. Nano Educ. 3, 5161, 2011


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Blonder and Dinur Teaching Nanotechnology Using Student-Centered Pedagogy for Increasing Students Continuing Motivation

mass spectroscopy using basic physics concepts, so that

high-school students will have contact with recent topicsof modern research. Planinic & Kovac (2008) developed

a teaching model for demonstrating the working principlesof Atomic Force Microscopy (AFM). Since AFM plays

an important role in developing nanotechnology, using this

teaching model supports the introduction of nanotechnol-ogy for the high-school level (Blonder, 2011). The above

examples provided teachers with teaching models whoseaim was to assist them in introducing contemporary sci-

ence in their lessons.

Learning advanced scientific issues can also be achievedby discussing socio-scientific issues, or teaching about

ethics and dilemmas that are based on scientific content,as recommended by (Hingant and Albe, 2010). Societal

implications of nanotechnology can be applied in a vari-

ety of areas, including technological, economic, environ-mental, health, as well as educational, ethical, moral, and

philosophical. Sweeney (2006) developed a nanotechnol-

ogy ethics seminar series, concerning social and ethicalissues associated with nanotechnology research. The sem-

inars focused on giving examples of potential social andethical issues associated with basic concepts of nanotech-

nology. In a survey of students and faculty members, he

found that students indicated a high level of interest inthe topics raised and discussed in the nanoethics semi-

nars, which, it appears, had prompted them to think moreabout the social, ethical, and environmental implications of

nanotechnology research than they otherwise might have

(Sweeney, 2006).A different way to adapt advanced contents to high-

school students level is to use constructivist pedagogy,in which the students are at the center of the learning

process. Moving from teacher-centered to student-centered

pedagogy switches the control of the learning environ-ment from the teacher to the learners, and according to

Pascarella, et al., (1981), it should affect students contin-

uing motivation.

1.1.2. Student-Centered Pedagogy

The concept of student-centered learning has been credited

to Deweys work (Dewey, 1902). Carl Rogers, the fatherof client-centered counseling, is associated with expanding

this approach into a general theory of education. In his

book Freedom to Learn for the 80s (Rogers, 1983), hedescribed the shift in power from the expert teacher to

the student learner, driven by a need for a change in thetraditional environment where in this so-called educationalatmosphere, students become passive, apathetic, and bored.

The student-centered approach is based on the hypoth-esis that students who are given the freedom to explore

areas based on their personal interests, and who are accom-

panied in their striving for solutions by a supportive,

understanding facilitator, not only achieve higher academic

results but also experience increased personal values,such as flexibility, self-confidence, and social skills. Thisapproach, also known as experiential learning, requiresspecific personal attitudes on the part of the instructor, who

takes over the role of a facilitator (ONeill and McMahon,2005).

These attitudes are highly transparent; instructors openup channels of communication and have positive attitudes

toward students and their search for deep understanding(Rogers, 1983). Although the positive effects of the purestudent-centered approach have been proved in a num-ber of case-studies and are well-documented in the lit-

erature (Chase and Geldenhuys, 2001; Lonka and Ahola,1995; Rogers, 1983), its combination with advanced mod-ern content as a resource for acquiring knowledge and asa medium for supporting communication is a novel asset.

In light of these considerations, two decisions wereincorporated into the design of the current teachingmodule:I. To design a teaching module in which the control in the

classroom will be shifted from the teacher to the students,using student-centered pedagogy.II. To build the teaching module around a modern topicin chemistry and nanotechnology that represents high use

of chemistry.

1.2. Description of the Module: LED via

Student-Centered Pedagogy

A light-emitting diode (LED) is a semiconductor light

sourcea

. LEDs are used as indicator lamps in many devicesand are increasingly used for other lighting. LEDs presentmany advantages over incandescent light sources includ-ing lower energy consumption, longer lifetime, improved

robustness, smaller size, faster switching, and greater dura-bility and reliability, and are one of the know nanotech-nology application.

Structure: The module was built around three guidedinquiry activities that were designed to trigger the stu-

dents questioning behavior. Each of the activity lasted twolessons and was followed by two lessons involving smallgroups work and a summary in the plenary session. During

the last two lessons of the activity, the students receiveda worksheet summarizing the whole module. This lessonended with a concluding summary of the module. Studentworksheets and final assignment were translated and areshown in the Appendix.

The activities within the module: As previously mentioned,the module included three guided inquiry activities. Table Ipresents the three experiments, their activities, goals, andthe reasons for choosing them as the triggering activity

during the module. The students working sheets for the

aLED definition was retrieved from: dictionary.com: http://dictionary.

reference.com/browse/led

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http://dictionary/http://dictionary/


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Table I. Three triggering activities that comprised the module, their description and goals.

Activity name Description The triggering effect Goals

1. Diode as a component in

an electric circuit.

Measuring the conductivity of different

components and different materials, and

examining the conductivity direction.

A diode is a component that only

allows electricity to flow in one

direction.

Triggering the students curiosity

regarding the diode structure,

which determines its unique

properties.

2. Color mixing versus light

mixing.

(a) Students mix gouache and create

different colors. They also use white and

black color to create light and dark

colors.

(a) In contrast to the mixing

gouache primary colors, mixing

colored light beams produces

different resulting colors.

Triggering the students curiosity

regarding the concepts of light

and color.

(b) Students mix different colored light

beams in an educational experiment.

They try to create the same colors as

they made from the gouache.

(b) Mixing together all the gouache

primary colors results in black,

but mixing the light beams results

in white

3. Comparison of the

standard lamp to the LED

lamp.

(a) Examine the efficiency of each lamp by

illuminating an object within a black box.

In contrast to the reasonable concept

that luminosity increases with the

size of the bulb and with the

strength of the battery, this

experiment reveals that the LED

lamp is as efficient as an

incandescent lamp that is three

times bigger than the LED.

Understanding the advantages of

LEDs and their unique

applications.(b) Disassembling the lamps and examining

their bulb size and battery size.

activities are presented in the Appendix. These three activ-ities were selected because they gradually build the basic

content matter for understanding the uniqueness of LEDand the way it works.

The learning process in this module was based totallyon students questions, aiming at guiding them to find theanswers to their own questions. The first activity (Table I)revealed the students lack of basic knowledge regardingelectric circuits. Their questions helped the teacher focuson the knowledge they wanted to learn (Baram-Tsabari

et al., 2006), as presented in Table II. In the next meeting,the students received two adapted scientific texts about thefollowing:(1) the electric circuit and what flows within it, and(2) silicon: its properties and its behavior as a semicon-ductor.

Reading these papers aided students in finding answersto their own questions that were asked after the firstexperiment. The new knowledge was summarized by theteacher, who highlighted the concepts of conductivity and

Table II. Examples of students questions during the different activities.

Experiment name Example of students questions

1. Diode as a component in an electric circuit What flows within the electric circuit?

What is a diode?

What material is it made of?

Why does the diode allow electricity to flow in one direction?

2. Color mixing versus light mixing Why there is a difference between mixing gouache primary colors and

mixing colored light beams?

What is color?

How could it be that mixing all the colored light beams gives white color and not black?

3. Comparison of the standard lamp to the LED lamp How could it be that a small size LED gives a high intensity light like a big

standard lamp?

Why the batteries used for LED lamp are smaller than a standard lamp?

What is LED? And from where does the light come from?

the differences between a conductor, semiconductor, and

isolator. She explained the way in which electrons areorganized in a semiconductor and the effect of p-doping

and n-doping.The second activity (Table I) led to learning the topic of

light as consisting of electromagnetic waves and different

light colors and their correlation to their photon energy.Students questions resulting from this activity are pre-sented in Table II. In trying to understand the source for

different light colors, the teacher demonstrated an exper-iment in which fire was lit in different colors by using

different metal salts. This experiment involved the LED,which emits light as a result of recombining an electronand a hole. The students compared the regular diode

they had encountered in the electric circuit that emits heatand the LED, which emits light.

Before the third activity (Table I), which dealt with

the advantages of the LED, the students received a paperthat described the different applications of LEDs. Stu-

dents questions resulting from this activity are presented

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in Table II. In summarizing the experiment, the studentsprepared a table that presented the advantages of LEDsderived from the experiment. They tried to explain thoseadvantages and to base their explanations on the previouslessons. The applications that were based on each of theadvantages were added to the table in the plenary session.

2. RESEARCH QUESTIONS

As mentioned, teaching the topic of LED by using student-centered pedagogy has the potential to increase studentscontinuing motivation. LED is an example of a mod-ern topic in nanochemistry, which has many applications.According to Pascarella et al. (1981), learning relevant top-ics that are useful to the students positively affect theircontinuing motivation. The student-centered pedagogy willalso contribute to the development of continuing motiva-tion since it shifts the focus of control from the teacher

to the learner and, according to Pascarella et al. (1981)and Vedder-Weiss and Fortus (2011), this shift also has a

positive effect on students continuing motivation. In thecurrent study we will examine those assumptions.

Thus, our research questions are as follows:(1) How did teaching a modern nanotechnology topic(LED) affect students continuing motivation?(2) How did using a student-centered pedagogy whileteaching a modern nanotechnology topic (LED) affect stu-dents continuing motivation?

3. METHODS

3.1. Participants

Thirty-six girls aged 15, in 10th grade, in two classes(N= 36), were chosen for the research. The second authorwas the chemistry teacher of these classes; she had tenyears of experience in teaching chemistry all of them

at this school. These groups were chosen because theyconsisted of students that did not enroll in chemistry, andwho had low attitudes toward chemistry in general (as wasobtained from the pre-attitudes questionnaire). The schoolis a high school for religious girls, located in the center of

the country.

3.2. Research Tools

The data that we were interested in referred to the maingoal of the study, namely, determining how the teach-ing module influenced students continuing motivation inchemistry. The data consisted of a pre-post attitudes test, asummative knowledge test, students interviews, and class-room observations documented by records and transcrip-tions of the course. The analyses of the interviews, thesurvey, and the transcriptions were done according to basic

methods of qualitative data analysis (Glaser and Strauss,

1967; Glesne, 2006), the main categories was determinedaccording the research questions and the subcategoriesemerged from the data. We also used a pre-post seman-tic differential (SD) test and a students final assignmentsand follow after the enrollment percent of the students intochemistry. In the following section we will elaborate oneach analysis of the data collection.

3.3. Quantitative Tools

3.3.1. Students Attitudes: Semantic Differential (SD)

Student Questionnaire

Use of the SD questionnaire was developed by Osgood,Suci, and Tannenbaum (1957). In the SD questionnaire,we used sets of words that could be used by students todescribe a learning situation (e.g., Easy vs. Difficult;Enjoyable vs. Not enjoyable; Monitored by the teach-ers vs. Monitored by me as well as by the teachers).

The students were asked to complete two SD question-naires: one before learning the module and one immedi-ately after learning it. Both SD-questionnaires containedthe same 28 sets of bipolar terms. In the pre SD, stu-dents were given the following instructions: Below aredescriptive pairs of words relating to studying chemistry inmy class. The terms of every pair were opposite in theirmeaning. Students were asked to mark the appropriatesquares between the terms. In the post SD, students weregiven the following instructions: studying the LED mod-ule. The words in every pair are opposite in their meaning.Please write an X in one of the squares between the words

that most express your attitude toward the two words.The SD questionnaire was developed by seven chem-istry teachers and a researcher in Chemistry Education; itcovers six categories, as described in Table III. The -Cronbach Reliability Coefficient was used to analyze 280questionnaires (including the experiment group) in orderto determine the validity of the categories, as presentedin Table III. Table III indicates that the six categories hadacceptable alpha reliabilities.

3.4. Enrollment in Chemistry

The number of students that enrolled in chemistry will be

recorded and compared to previous years. The comparisonis reliable since this school has the same type of studentsevery year: religious girls that come from the same com-munity. This tool will enable us to compare how the inter-vention affected students continuing motivation in relationto previous years in which no intervention was taken.

3.5. Qualitative Tools

3.5.1. Students Interviews

The student interview is a powerful qualitative tool used

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Table III. Descriptive information for and reliability of the SD questionnaire.

-Cronbach

Category Number of items Sample item reliability coefficient

Was the module relevant to students lives? 6 In the Chemistry lessons I learn about

topics concerning my own life.

0.82

Was the module interesting? 5 I find the chemistry lessons very

interesting.

0.82

Was the module student centered? 3 I contributed to the way the lessons

were developed.

0.63

Did the module develop cognitive skills? 4 The Chemistry lessons include activities

that help me understand the subject.

0.62

Did the module promote continuing motivation? 6 I read at home about the subject that

was taught in the chemistry lessons.

0.78

Did the module present chemistry as a modern subject? 4 In chemistry lessons we learn about

contemporary science.

0.70

of educational investigations utilize interview data, espe-cially when the aim is to investigate students percep-tions (Glesne, 2006). With the present research, ninestudents (25%) were interviewed after they had learnedthe LED module. A structured interview was used; all

the participating students were asked a series of specificquestions: Can you indicate some differences between the LEDmodule and regular science lessons? Did you share the learned knowledge with someone notin the class? Does learning the module influence your plans regarding

enrollment in chemistry next semester? Do you recommend teaching this module next year (forother students)?

We elected to begin the interview by asking the stu-dents to indicate the differences between the LED moduleand a regular science lesson because we wanted to cap-ture the differences they would find without help from theinterviewer.

All interviews were recorded and transcribed before

analysis. The interviews were analyzed according to twomain categories: continuous motivation and the factors thataffect students motivation.

3.6. Transcriptions of the Course Meetings

The course meetings were audio recorded and the dis-cussions held during the lessons were transcribed. Fromreading the transcriptions, we learned about the studentsperceptions regarding their learning and their learningenvironment, as well as their specific difficulties. Thesetranscriptions also helped us triangulate the data that werecollected from the interviews and analyzed according to

the same categories.

3.7. Students Final Assignments

At the end of teaching the module, the students received a

summative assignment. Since the goals of the intervention

focused on continuing motivation, preparing and submit-

ting the final assignment was not compulsory. The final

assignment included a scientific text about LED that was

taken from a web-article Weaving with Light (Sohn,

2007), which was followed by questions from different

understanding levels (based on Blooms taxonomy (Bloom

and David, 1956)). The teacher used this assignment to

evaluate students understanding of the learned topic. In

the current paper the final assignment was used as an indi-

cator of students motivation, as will be presented in the

Results section (4.5).

4. RESULTS

4.1. Students Attitudes: The Semantic Differential

(SD) Student Questionnaire

The Semantic Differential (SD) questionnaire was aimed

at mapping students perceptions after they learned the

LED module. The SD questionnaire was analyzed using

the Wilcoxon Signed Rank test, and the change in stu-

dents perceptions (post-pre) is presented in Figure 1.

A significant, positive change in attitude regarding the

relevance items in the SD questionnaire was recorded

Fig. 1. How learning the LED module affected students attitudes

toward the six examined categories. The Wilcoxon Signed Rank test was

applied to the SD results. p < 005, p < 001, p < 0001.

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(p < 0001), more specifically, the items related to Mod-

ern chemistry (p < 005), the items related to Continuingmotivation (p < 001), and the pedagogy of emphasizing

student-centered activities was scientifically positive (p

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