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Jun 15, 2011 - ABSTRACT: Polymers are materials with vast environmental and economic ramifications, yet are generally not discussed in secondary educa...
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College-Mentored Polymer/Materials Science Modules for Middle and High School Students Robert G. Lorenzini,† Maurica S. Lewis,‡ and Jin Kim Montclare*,†,§ †

Department of Chemical and Biological Sciences and ‡Department of Chemical and Biological Engineering, Polytechnic Institute of New York University, Brooklyn, New York 11201 United States § Department of Biochemistry, SUNY-Downstate Medical Center, Brooklyn, New York 11203, United States

bS Supporting Information ABSTRACT: Polymers are materials with vast environmental and economic ramifications, yet are generally not discussed in secondary education science curricula. We describe a program in which college mentors develop and implement hands-on, polymerrelated experiments to supplement a standard, state regents-prescribed high school chemistry course, as well as a middle school elective course on polymers. Interactive experimentation and feedback-oriented design are highlighted as critical elements to the success of the program. The experiments have been executed in two vastly different institutions: a New York City magnet high school for underprivileged females, and a private middle school for privileged male and female students; the similarities and differences are juxtaposed. KEYWORDS: Elementary/Middle School Science, High School/Introductory Chemistry, Chemical Education Research, Polymer Chemistry, Public Understanding/Outreach, Collaborative/Cooperative Learning, Hands-On Learning/Manipulatives, Materials Science, Minorities in Chemistry, Women in Chemistry

’ BACKGROUND Women and minorities are underrepresented in many “technical” fields, including chemistry.1,2 A number of initiatives have been undertaken to combat this anomaly, such as the specific recruitment of women and minorities by institutions,3 the genesis of effective mentoring programs aimed at young women and minorities,4 and the formation of specialized schools and programs.5 There is a great interest in the performance of charter and charteresque schools as the American Recovery and Reinvestment Act of 2009 specifically allocated funds for the establishment of new, specialized charter schools under the Race to the Top initiative.6 The Urban Assembly Institute of Mathematics and Science for Young Women (UAI), a New York City quasi-charter high school located in Brooklyn, New York, is one of the aforementioned specialized programs. This school encourages careers in science (and by extension, a college degree) for a predominantly minority and underprivileged group of all-female students. Our program, funded by both The Dreyfus Foundation and The National Science Foundation Materials Science and Engineering Center, originally sought to design three polymer and materials science-themed lesson plans (dubbed “modules”) to be offered during 75-min blocks of class time, serving approximately 70 underprivileged female ninth grade students at the UAI. Based on dissemination of this project through our Web site,7 the college mentors were contacted and asked to conduct the modules for approximately 30 more students at the Horace Mann School (HM), a private, mixed-age school serving privileged male and female students. Here, the college mentors worked with eighth graders enrolled in a polymer science elective course. Hands-on, interactive science education is a crucial supplement to standard didactic instruction.8 All of the instructional Copyright r 2011 American Chemical Society and Division of Chemical Education, Inc.

objectives of our group always included a hands-on activity. This approach proved to be successful: UAI students consistently requested more in-depth, hands-on activities. Before the modules were exposed to the UAI students, the college mentors tested the lab activities with young family members to ensure clarity and simplicity. Of the 70 students that were involved at the UAI, 89% were African-American and 11% were Latino, according to demographics provided by their teacher. While the demographics of the 30 Horace Mann students were not provided, the students involved were predominantly Caucasian by observation. Both the UAI and HM teachers were Caucasian women. One male and one female college student, both 21-year olds, were selected to serve as mentors for the program. The male college mentor was Caucasian and a fourth-year chemistry major who had previous tutoring experience at both the high school and college levels. The female college mentor was of Antiguan nationality and a third-year chemical and biological engineering major who had previous experience as a counselor working with youth between ages 10 and 16. The original expectations of this program were as follows: 1 Provide hands-on teaching and social experience for two college mentors. 2 Assist a chemistry teacher in an underprivileged high school. 3 Foster chemical education, with an emphasis on polymers, among an underserved group of high school students. 4 Disseminate these results and modules for the benefit of the field of chemical education. Published: June 15, 2011 1105

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Journal of Chemical Education After the modules were requested at HM, expectations grew to include the following: 5 Assist a middle school teacher from a different school. 6 Instruct a set of privileged eighth grade students. 7 Compare trends and results across both schools. All of the modules described in this paper as well as the teacher’s manuals are provided in the Supporting Information. Examples of similar laboratory exercises were found in the literature,9,10 but were complex and used materials dangerous for young students. In order for us to employ hazardous chemicals in the program, additional permission from the school and parents was required. Thus, we decided to design modules that did not require the use of harsh chemicals. Two similar exercises11,12 offered additional, safe polymer experiments suitable for young students. In contrast to these programs,912 our modules were specifically designed for students from economically disadvantaged backgrounds, many of whom have gaps in their scientific and mathematical knowledgebase. The modules were designed to convey complex scientific principles in the simplest words possible.

’ RESULTS The Modules

The first module, Lab Skills and Rubber Balls, was designed to present the notion that polymers are made of simple, repeating units, or monomers. To introduce the concept of polymers, a simple and extremely effective exercise was to have the students use their names to create a polymer (for example, Poly(John) would be JohnJohnJohn), which demonstrates their repetitive nature. The hands-on section involved the synthesis of rubber balls from white glue and a mixture of borax and cornstarch, varying the concentrations of reactants to change the macroscopic properties of the balls. The students tested the balls that they made by bouncing them from a fixed height marked on the wall, emphasizing that changing the mixture has an effect on bouncing. The second module, Hydrogels, was an exposition into the absorbent properties of sodium polyacrylate. The students obtained the material from diapers and compared its effectiveness in absorbing pure water versus salt water (with salt water serving as a hygienic replacement for urine). To present the students with the notion of sterics within polymers, this lesson focused on how polymers swell, and how salts affect concentration gradient-dependent processes. The students recorded how much pure water it took to break the diapers open as opposed to the amount of salt water. Because sodium polyacrylate absorbs pure water much better than salt water, less water was needed to saturate the diaper. The use of diapers also introduced the idea that polymers are used in various aspects of everyday life. The third and final module, Biodegradable Materials, taught students the importance of recycling with respect to synthetic polymers and biopolymers. In class, a calculation was performed to demonstrate that if one were to drink two water bottles a day for a lifetime, one would create nearly 850 kg of long-lasting waste. The activity entailed putting a sheet of toilet paper composed of cellulose (a biopolymer) and a similarly sized sheet of polyethylene cut from a plastic bag (a synthetic polymer) in vinegar. The mixture was then stirred to prove that the polyethylene would not degrade by simple means. At the beginning of each session, the college mentors prepared all of the laboratory materials. Students then received a paper

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Figure 1. Module submission frequency at the UAI.

copy of the module, and the opening paragraphs were read aloud by the college mentors. The college mentors then gave between 10 and 20 min of lecture instruction, including the theory of the activity and detailed laboratory instructions, after which the high school students completed the activity themselves. All throughout the activity, the college mentors supervised and answered any posed questions from the UAI students. The college mentors worked closely with the high school teacher to tailor the modules and to establish dates of implementation in accordance with the UAI curriculum. The UAI teacher helped by editing the modules, approving them for use in her class, and answering students’ questions during the lab activities. After running the first module in the early fall at UAI, two facts became clear. First, the original modules had too many activities and questions to be completed in the 75-min allotted blocks, and second, an excess of scientific terms were alienating to the students. Because the UAI teacher was also new to the school and students, neither she nor the college mentors were able to anticipate this before implementation of the first module. As a result of the early difficulties related to excess jargon and overcomplicated directions, the second and third modules were modified. In the first module, students had problems with the wording of the directions in the lab activity. Future modules included simplified ideas and more conservative learning goals. The high level of module adaptability was a pillar in the success of this program as it was necessary as described above. Of the seven modules initially generated, three were selected and finalized based on the feedback received. A nylon synthesis module involving 1,6-diaminohexane and sebacoyl chloride was eliminated owing to the hazards of the reagents. Three different modules involving proteins and DNA were not used because the UAI teacher believed the topics were beyond the scope of their curriculum. While all three of the modules were taught at the UAI, only two of the modules were completed by the HM students. Each module was intended for a 75-min period, and only one 45-min block of time was allotted at HM, thus only the modules on Rubber Balls and Biodegradable Materials were implemented. This time constraint did not allow the college mentors to elaborate at HM as much as they did at the UAI. The overall effectiveness of the modules, however, was not compromised, as the HM students already had an extensive background in polymers. Module Submission and Positive Reinforcement: UAI

As part of the modules, the students were required to answer questions testing conceptual skills and to submit them to the college mentors for a grade to be included in their high school class average. Initial submission rates at the UAI were poor (as were the submission rates of teacher-assigned work), thus positive reinforcement in the form of prizes was introduced. For the first and second 1106

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Journal of Chemical Education

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Table 1. Distribution of Module Grades at the UAI

Table 4. Distribution of Module Grades at HM

grades 05, % of students

grades 05, % of students

module

0

1

2

3

4

5

module

0

1

2

3

4

5

1

24.9

40.7

14.8

14.8

3.7

0.0

1

0.0

0.0

0.0

12.0

20.0

68.0

2

23.4

19.1

25.5

19.1

8.5

4.3

3

0.0

0.0

0.0

0.0

13.0

87.0

3

0.0

0.0

8.7

40.6

24.6

26.1

Table 5. Average Module Grades at HM Table 2. Average Module Grades at the UAI module 1 grade, 05

module 2 grade, 05

module 3 grade, 05

1.30

1.83

3.68

module 1 grade, 05

module 3 grade, 05

4.56

4.87

Table 6. HM Student Module Grades for Completeness Table 3. UAI Student Module Grades for Completeness module

module completion, check system √ √ þ

module

√ 

1 2

18 19

9 13

0 15

3

0

3

66

modules, there was no mention of prizes. In addition to low submission rates, many of the modules submitted were incomplete. The use of positive reinforcement vastly improved our module submission rate. After the college mentors distributed prizes (lip gloss, hair-ties, other small beauty items) based on good performance on the first two modules, the amount of modules (Figure 1) and the quality of work submitted (Tables 1 and 2) increased enormously. The completeness of the modules also increased drastically (Table 3). Although immediate improvement in performance was seen, prize distribution is not a reliable method to encourage long-term intrinsic motivation in students. The implications of the need for positive reinforcement for personal development are vast and beyond the scope of this paper. It is worth noting, however, that schools in the United States have explored the possibility of paying students in underachieving districts for good performance,13 and, according to these data, such an approach results in a positive effect. By contrast, this complication was totally absent at HM as a vast majority of students submitted their work immediately after they completed the activity. The modules were graded on a scale of 05 based on conceptual understanding, with a 5 being the highest score possible. High school and middle school students were assigned a 0 when they left everything blank, and were awarded a 5 for a full grasp of the topic, with the grades decreasing based on the quality and length of the answers. A second grade was √ determined based on the√ completeness of the modules: a þ being √ totally completed, a  being blank, and a being satisfactorily completed. This allowed for a student to submit an incomplete module, but still have their grade reflect a good conceptual grasp of the part they did finish. The HM students had little difficulty with the modules. Because the HM students were allotted less time for the activities, whereas the UAI students were not rushed, their grades may not represent their full abilities. Nonetheless, the average grades and submission at HM were significantly higher than the grades at the

√ 

module completion, check system √ √ þ

1 3

1 0

3 6

21 17

total

1

9

38

UAI (Tables 4, 5, and 6), despite less instruction from the college mentors, and a one-year age difference of the students.

’ A LOOK BACK AND CONCLUSIONS We consider the program to be generally successful for several reasons. For the UAI, the most important lesson imparted on for the students was simply the fact that chemistry is very much a part of everyday life. Observations made at UAI indicated that many students compartmentalized their home lives and school lives. The use of modules incorporating elements from day-today life (plastic bags, diapers) is effective in making the message easily understandable. The students developed a newfound appreciation for recycling and the potential impact of polymeric waste—an important notion to instill in young citizens of the world. Importantly, the UAI students were exposed directly to college students who were pursuing science and engineering degrees, providing them a role model for their futures. For HM, the modules fit perfectly within the scope of their polymer science elective class. This seemed to be less of a learning activity, and more of an enhancement and reinforcement of coursework. The presence of the college mentors themselves was truly the unique part: one of the HM students commented, “you’re cool” to one of the college mentors, perhaps dismantling the common stereotype that scientists are “boring”. The college mentors gained invaluable teaching and social experience. They learned the importance of patience and communication in the educational process, and how to collaborate to overcome difficulty in the implementation process. The college mentors were also afforded a “behind-the-scenes” look at the arduous process of education: having to purchase and set up materials provided an entirely different perspective than being catered to, as is customary for undergraduate student laboratories. The modules at HM were executed with no problems and with no obvious room for improvement. With respect to the UAI, various shortcomings in our methodology and nonrelated 1107

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Journal of Chemical Education obstacles were realized. The following conclusions were made for the strengthening of a future program: (i) it is necessary to develop a closer relationship with the high school students; (ii) it is necessary to find an effective and suitable means of motivation; and (iii) it is necessary to maximize teacher involvement. Developing a Closer Relationship between the College Mentors and High School Students

The modules were administered at the UAI on Fridays, allowing the college mentors three days’ worth of instructional face time, with a few more for administrative duties (module evaluations, prizes, etc.). Throughout the year, the development of a relationship between the college mentors and high school students was not as rapid as the relationship between the high school students and their teacher, likely owing to the teachers’ increased interaction time with the students. Perhaps a more developed relationship between the college mentors and the students would have made the lessons and mentoring more effective. Finding a Way To Motivate Students

The UAI teacher noted that homework submission and class work completeness was normally less than adequate, which provided the inspiration for us to try to motivate students by rewarding good performance. There was a vast increase in performance and submission by the final module after the tokens and prizes were given out. While the prizes appeared to motivate the students, the use of tangible rewards is a controversial issue because it is desired that students become motivated intrinsically to perform well in the long term. As an alternative to extrinsic prizes, rewards in forms of verbal encouragement and classroom privileges so that students have ownership of the classroom materials are other options we intend to pursue.14 Maximizing Teacher Involvement

While the UAI teacher assisted the college mentors in inspecting and critiquing the modules as they were being developed, the college mentors implemented the modules on their own. Participation of the teacher while the college mentors were administering the modules would have better integrated them within the curriculum. As this was the first time the teacher was working with the program as well as the UAI, encouraging teacher participation in the administration of the modules will likely improve the overall program. Most high school and middle school students do not get specific instruction in polymers and materials science, as this topic is generally not included in secondary education science curricula. The high school students involved in this program (students from radically different educational and social backgrounds) benefit both from obtaining polymer and materials science knowledge and by having direct contact with two college students actively engaged in the chemical sciences. Many of these high school students may not have the opportunity to interact with college students; the exposure to college mentors through this program may inspire them to pursue college degrees in science and engineering. The groups interacting—college mentors, the high school teacher, and students—provide a dynamic, knowledgeable, and accessible network of resources for all involved. The use of adaptable modules is the critical feature that improved the quality of education. It is anticipated that partnerships between universities and secondary schools as demonstrated here can potentially help address the lack of

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females and minorities pursuing higher education in scientific and engineering disciplines.

’ ASSOCIATED CONTENT

bS

Supporting Information Modules 13 with corresponding teacher's manuals. This material is available via the Internet at http://pubs.acs.org.

’ AUTHOR INFORMATION Corresponding Author

*E-mail: [email protected].

’ ACKNOWLEDGMENT This work was supported by the Dreyfus Foundation and partially by the MRSEC Program of the National Science Foundation under Award Number DMR-0820341. We would like to thank Jill Fonda and Ashley Miller, the UAI and HM teachers. We also thank Yan Mei Chan for great discussion and guidance throughout. ’ REFERENCES (1) Harris, C. M. Laboratories without Walls. Anal. Chem. 2002, 74, 535A. (2) Moore, J. W. Diversity in Science. J. Chem. Educ. 2006, 83, 823. (3) Adams, G. M.; Lisy, J. M. The Chemistry Merit Program: Reaching, Teaching, and Retaining Students in the Chemical Sciences. J. Chem. Educ. 2007, 84, 721. (4) Garrison, L. E. Growing the Positive Perception of Chemistry through Collaboration. J. Chem. Educ. 2006, 83, 1123. (5) Subotnik, R. F.; Tai, R. H.; Rickoff, R.; Almarode, J. Roeper Rev. 2010, 32, 7. (6) U.S. Department of Education. Press Releases—States Open to Charters Start Fast in ‘Race to Top’. http://www2.ed.gov/news/ pressreleases/2009/06/06082009a.html (accessed May 2010). (7) Chem-Bio Technology Lab. Polytechnic Institute of New York University. http://research.poly.edu/∼cbtl (accessed May 2011). (8) Haury, D.; Rillero, P. Perspectives on Hands-On Science Teaching; ERIC Clearinghouse: Columbus, OH, 1994; p 22. (9) Buchholz, F. L. Superabsorbent Polymers: An Idea Whose Time Has Come. J. Chem. Educ. 1996, 73, 512–515. (10) Cleary, J. Diapers and Polymers. J. Chem. Educ. 1986, 63, 422. (11) Sherman, M. Polymers, Polymers, Everywhere!: A Workshop for Pre-High School Teachers and Students. J. Chem. Educ. 1987, 64, 868. (12) Woodward, L.; Bernard, M. A. Evening Polymer Programs To Pique the Interests of Youngsters and Adults. J. Chem. Educ. 1993, 70, 1006. (13) Chen, M. Washington, D. C. Students Are Paid To Get Good Grades. Wayland Student Press Network, Jan 12, 2009. http://waylandstudentpress.com/2009/01/12/washington-dc-students-are-paid-to-getgood-grades/ (accessed May 2011). (14) Pink, D. Drive: The Surprising Truth about What Motivates Us; Penguin Books: New York, 2009.

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