Vanderbilt Student Volunteers for Science - Journal of Chemical

Currently, VSVS teams are working with teachers in 60 classrooms at five middle schools that involve about 1800 fifth and sixth grade students...
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John T. Moore Stephen F. Austin State University Nacogdoches, TX 75962

Vanderbilt Student Volunteers for Science

David Tolar R. C Fisher School Athens, TX 75751

Melvin D. Joesten* and Patricia C. Tellinghuisen Department of Chemistry, Vanderbilt University, Nashville, TN 37235; *[email protected]

Vanderbilt Student Volunteers for Science (VSVS) was organized in the spring of 1994 to give Vanderbilt undergraduate, graduate, and medical students an opportunity to present inquiry-based science lessons to fifth- and sixth-grade students. The primary goal of this university-wide student volunteer organization is to help middle school teachers enhance the science instruction in their classrooms by supplementing the middle school science curriculum with hands-on, inquiry-based lessons presented by VSVS teams. Objectives for members of VSVS are to provide volunteers with an opportunity to explain science to school children, help college students recognize their responsibilities for community service and the importance of volunteer service in schools, provide role models for school children, and stimulate interest in teaching as a profession. Many outreach programs have been described that involve college students visiting classrooms or giving workshops for middle school children and their parents (1). An elementary school outreach program in which high school students visit third, fourth, and fifth grade classes has also been described in this Journal (2). The unique aspect of Vanderbilt’s program is the development of a university-wide service organization that brings inquiry-based, hands-on activities to thousands of middle school students each year through both on-campus and off-campus programs. An essential component of our program is our collaboration with middle school teachers who recognize the importance of inquiry-based activities and are willing to have college students come to their classrooms to provide additional science activities for their students. Off-Campus Program We are currently working with teachers in 60 classrooms at five middle schools (involving about 1800 fifth- and sixthgrade students). VSVS teams of three or four are assigned to a fifth- or sixth-grade classroom where they present four lessons during an eight-week period, usually every other week. Each VSVS member gets a copy of the lesson manual for the grade level, and practice sessions are held at the beginning of each semester to give the teams an opportunity to work through the lessons before teaching them. Supplies for each lesson plan are provided in boxes that teams pick up before going to the school site. Since 1994, a variety of lesson plans have been developed, classroom-tested, and evaluated by teachers and VSVS members. Ongoing discussions with teachers have led to the development of new lessons on curricular topics that are difficult for the teachers to cover because of lack of equipment and supplies or because of the lack of appropriate published inquiry-based activities. For example, new lessons on chemical reactions, kinetic and potential energy, energy conversions,

and pulleys were developed to better relate the science curriculum to the National Science Education Standards (3). Many of the lessons include take-home activities.

Lesson Plans for Fifth Grade Fall Consumerism: Paper Towel Testing. This lesson, which is based on “Paper Towel Testing” by GEMS (4 ), introduces students to the challenges of comparing products scientifically. The strength and absorbing properties of four brands of paper towels are measured. Students calculate the cost per square foot of the different brands and determine which brand is the best buy on the basis of their testing results. Activities Involving pH. Several references provided ideas for appropriate activities on the study of acids, bases, and pH (5, 6 ). Students use red-cabbage juice as a visual pH indicator to test common household items with different pH values by comparing their color changes to the color changes for a series of 11 pH standard solutions. Students receive a take-home activity sheet that explains how to make red-cabbage juice and red-cabbage test paper. Examples of household items that can be tested are also described. Polymer Chemistry. Students are introduced to the concepts of polymers (7–11), and they investigate the properties of gluep (7, 11). The lesson begins with a discussion of the difference in relative movement of molecules in solids, liquids, and gases. This is followed by the use of models to show how individual molecules join to form large molecules called polymers. Students are given a take-home activity sheet with information about making oobleck (12) and gluep and directions for studying their properties. Light. Prisms, diffraction gratings, and flashlights are used to study reflection and refraction of light. The difference between white light and single-wavelength laser red light is then demonstrated using a flashlight and a laser pointer. Pieces of fiber-optic cable are used to study total internal reflection and important applications of fiber-optic cable in carrying images (cable TV, computer networking) or optically transmitted telephone messages are discussed. Students receive a take-home activity sheet with experiments to help them understand why the sky is blue and clouds are white. Spring Cryogenic Temperatures. Liquid nitrogen is used to demonstrate the effects of very low temperatures on the properties of materials. The lesson also demonstrates re-forming solid dry ice by pouring liquid nitrogen over a balloon filled with carbon dioxide gas (produced by adding water to pieces of dry ice in a 16-oz plastic beverage bottle fitted with a balloon.) The lesson concludes with the preparation of two-minute ice cream using liquid nitrogen as the coolant.

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Minerals: The Building Blocks of Rocks. This lesson introduces students to some of the tests that geologists use to determine the properties of minerals. Students carry out a series of tests on five minerals (muscovite, talc, magnetite, calcite, and rose quartz) and record their observations. The tests include appearance, magnetism, streak, hardness, and reaction with 0.5 M hydrochloric acid. The results of the tests for each mineral are discussed. Properties of Carbon Dioxide. Students study the properties of carbon dioxide. The lesson begins with a discussion of the formula of carbon dioxide, CO 2, and what it means. The students then compare the properties of dry ice, the solid form of CO2, to the properties of water ice. Chemical reactions to make CO2 are also included in the lesson. Pulleys. Students collect data on single and double pulleys in various configurations to learn how pulleys work. The lesson compares the mechanical advantage of a single fixed pulley, a single moveable pulley, a double fixed pulley, the combination of a single fixed pulley with a single moveable pulley, and the combination of a double fixed pulley with a single moveable pulley. Students use the results of their measurements to calculate mechanical advantage.

Lesson Plans for Sixth Grade Fall Chemical Reactions. Students use microscale chemistry procedures with reagent dropping bottles and a 24-well culture plate to mix reagents that form a precipitate or a gas, or give a color change (Fig. 1). Chromatography. This lesson introduces students to a technique for separating mixtures that is used by biologists, chemists, clinical scientists, and forensic scientists (13, 14 ). The lesson begins with an activity on capillary action or the wicking property of water and how this can be used to separate colors. After separating green into blue and yellow on different types of paper using water as the solvent, students run chromatograms to determine which of four pens was used to write a ransom note. They receive a take-home activity sheet that describes ideas for science fair projects on chromatography. Energy Conversions. Students learn about a variety of energy conversions through demonstrations and hands-on activities. The following energy conversions are included: chemical to electrical (measuring voltages of different metals inserted in a lemon), electrical to chemical (electrolysis of water), chemical to heat (chemical hand-warmers), chemical to light (glow stick), and light to electrical (solar cell hooked to digital clock). Potential and Kinetic Energy. The difference between potential and kinetic energy is studied by looking at energy changes in the conversion of kinetic energy to potential energy. The effect of height on potential energy is studied using model cars on tracks at different heights. The effect of mass on kinetic energy is studied by comparing the distance traveled on a track by model cars of different mass. Spring Diffusion. The lesson includes activities to help students understand diffusion, the selective movement of molecules through membranes of different porosity. Students use baggies and dialysis tubing to determine whether there is a difference 464

Figure 1. Sixth grade students doing chemical reactions lesson.

between the passage of glucose molecules and of starch molecules through these different membranes. Glucose test strips are used to test for glucose and an iodine solution is used to test for starch. Two-dimensional scale drawings of the iodine, glucose, and starch molecules help emphasize the difference in size of the molecules and how this relates to the porosity of the membranes. Tracing an Epidemic. Students trace an epidemic and how a disease spreads by using 0.025 M sodium hydroxide to represent the disease carrier and phenolphthalein to determine the carrier and who has been “infected”. Food Chemistry. Students carry out known tests on fats (potato chips), carbohydrates (flour) and proteins (powdered egg whites) in foods. Students then test peanuts, crackers, instant mashed potato flakes, and coconut flakes to determine whether each food has primarily one nutrient or a mixture of nutrients. Rates of Chemical Reactions. The lesson includes activities to help students understand factors that affect the rates of chemical reactions—temperature, concentration of reacting substances in solutions, surface area (particle size) of solids in reactions with gases and liquids, and catalysts (15). On-Campus Program Day on Campus (DOC) gives every sixth-grade student (about 5200) in Metropolitan Nashville public schools the opportunity to visit Vanderbilt University for a day. Approximately 60 students come to campus each day. Begun in 1990 by the Vanderbilt Office of University Relations, the program’s goal is to encourage students to stay in school and to consider attending college. The sixth-graders are brought to campus by a school bus, and after they arrive, they are divided into two groups. Each group receives a tour of campus and attends 30-minute classes in art history and chemistry, which are held in the student center. The chemistry classes for the two groups are given back to back between 11 a.m. and 12 noon by a VSVS team who teach a lesson on polymers (7– 11). The lesson includes a short introduction on what polymers are, followed by a demonstration of the superabsorbing properties of sodium polyacrylate. Then students make their own slime by mixing solutions of polyvinyl alcohol and borax (8).

Journal of Chemical Education • Vol. 78 No. 4 April 2001 • JChemEd.chem.wisc.edu

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80 Figure 2. Distribution of VSVS members by school.

Figure 3. Distribution of VSVS members by class.

The students get to take their slime with them, and they also receive a take-home activity sheet with information about making oobleck, gluey putty, and goop and directions for studying their properties. During the session, the sixth-graders are given a chance to ask the VSVS team members questions about college life. A team of three VSVS members is assigned to teach the lesson the same day each week.

These included tutoring school children after school, judging science fair projects, helping with Saturday computer camps for middle school children, teaching science activities as part of their alternate spring break project, doing hands-on science activities for after-school programs and parents’ night, and presenting chemistry activities during National Chemistry Week.

Medical Student VSVS Elective Since January 1995, Vanderbilt University Medical School has offered a one-hour elective course with VSVS. Once a week, medical students in the course visit a fourth-grade classroom to engage the students in interactive activities. Medical students work in teams of two and they develop four lessons based on biomedical topics. In fall 1999 the lesson topics were DNA and the Cell Cycle, Heart and the Circulatory System, Bones and the Skeleton, and Examining the Perception of Taste. Each lesson was taught to two different classes. Student Volunteers During the 1999–2000 academic year, 308 students were involved in VSVS activities during the fall and spring semesters; 149 participated both semesters. Approaches used to recruit volunteers at the beginning of the academic year include (i) extensive advertising with campus posters, table tent announcements in dining halls, flyers in science labs, and faculty announcements in science courses, (ii) a table at the Student Activities Fair where VSVS board representatives answer questions, and (iii) email messages to volunteers from previous years. Several of the same methods are used at the beginning of the spring semester with emphasis on email messages to those who volunteered in the fall. Figure 2 gives the number of volunteers from the College of Arts and Science (A&S), School of Engineering (ENG), George Peabody College of Education (GPC), and Blair School of Music (BLR). The GRAD section includes five chemistry graduate students and 12 medical students. Figure 3 shows the number of volunteers by class. During the 1999–2000 academic year, VSVS members also volunteered for a number of related outreach activities.

Organization of VSVS Running a program of this magnitude requires a strong organizational structure. Volunteer staff include the faculty advisor and the VSVS Student Board. Paid staff include a half-time coordinator and six student workers. The VSVS coordinator calls teachers to arrange for classroom visits by VSVS teams, organizes schedules for VSVS class visits and matches teachers with VSVS teams, supervises Vanderbilt student workers who prepare and refurbish lesson kits for both on-campus and off-campus programs, helps develop new lesson plans, obtains teacher evaluations of VSVS teams, attends meetings of the VSVS Student Board, and shops for consumable supplies. The faculty advisor works with the coordinator, develops new lesson plans, helps supervise the student workers, and meets with the VSVS Student Board. The 10-member VSVS Student Board is actively involved in the ongoing operation (16 ). They are responsible for recruiting new members and they handle all the publicity and planning for organizational meetings held at the beginning of each semester. Board members periodically call VSVS teams to check on how they are doing. Board members also lead practice sessions on the lessons at the beginning of each semester. The program is primarily funded by Vanderbilt University through the Office of Community Relations with additional funding from the Tennessee Space Grant Consortium. Acknowledgments Michael Schooling, a medical student in 1994, deserves recognition as the cofounder of VSVS with MDJ. We also acknowledge the help of Susan Clendenen, a teacher in the Nashville Metropolitan schools, for her assistance in developing and class-testing some of the lesson plans.

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Literature Cited 1. Koehler, B. G.; Park, L. Y.; Kaplan, L. J. J. Chem. Educ. 1999, 76, 1505–1509, and references cited therein. 2. Swim, J. J. Chem. Educ. 1999, 76, 628–629. 3. National Research Council. National Science Education Standards; National Academy Press: Washington, DC, 1996. 4. Sneider, C. I.; Barber, J. Paper Towel Testing, Teacher’s Guide; Lawrence Hall of Science, University of California: Berkeley, 1990. 5. Sae, A. Sci. Teach. October, 1990, 57 (Oct), 17–18. 6. Fun with Chemistry, Vol. 1, 2nd ed.; Sarquis M.; Sarquis, J., Eds.; Publ. 91-005; Institute for Chemical Education, University of Wisconsin: Madison, 1991; pp 53–62. 7. Journal Editorial Staff. J. Chem. Educ. 1998, 75, 1432A. 8. Fun with Chemistry, Vol. 2; Sarquis M.; Sarquis, J., Eds.; Publ.

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93-001; Institute for Chemical Education, University of Wisconsin: Madison, 1993; pp 67–76, 81–88, 95–99. Casassa, E. Z.; Sarquis, A. M.; Van Dyke, C. H. J. Chem. Educ. 1986, 63, 57–59. Sarquis, A. M. J. Chem. Educ. 1986, 63, 60–61. Woodward, L; Polymers All Around You; Terrific Press: Middletown, OH, 1993. Sneider, C. I. Oobleck, Teacher’s Guide; Lawrence Hall of Science, University of California: Berkeley, 1996. Fun with Chemistry, Vol. 2; Sarquis M.; Sarquis, J., Eds.; Op. cit., pp 3–8. Barber, J. Crime Lab Chemistry, Teacher’s Guide; Lawrence Hall of Science, University of California: Berkeley, 1985. JCE Editorial Staff. J. Chem. Educ. 1998, 75, 1120A. See VSVS Online; http://www.vanderbilt.edu/vsvs (accessed Jan 2001).

Journal of Chemical Education • Vol. 78 No. 4 April 2001 • JChemEd.chem.wisc.edu