Chemistry Everyday for Everyone
ChemKits: A Teacher-Training and Instrument-Sharing Project Mike Mitchell Vice President and Academic Dean, Bethany College, Lindsborg, KS 67456 David Shubert* Department of Chemistry, Newman University, Wichita, KS 67231;
[email protected] Carolyn Herman formerly at Department of Chemistry, Southwestern College, Winfield, KS 67156-2499
Lack of laboratory instrumentation in the high school science curriculum has been a concern for some years (1). Quality Performance Accreditation, a reform initiative in Kansas public elementary and secondary schools, has forced teachers to redesign curricula. In 1992 these factors led Kansas independent (private) colleges to examine the needs of Kansas high school science teachers in the hope of identifying areas where colleges could provide assistance. Mail surveys and a focus group meeting of high school chemistry teachers indicated that students received very little hands-on experience with laboratory instrumentation. This situation was particularly severe in inner-city and rural school districts. School budgets were not sufficient to purchase such equipment, nor were faculty prepared to use it effectively in class. Some form of instrument sharing (2–5) coupled with teacher training seemed to be a cost-effective solution. Several constraints were applied in selecting appropriate instrumentation. So that high school students could draw valid conclusions from experiments, instruments had to collect and process experimental data with reasonable accuracy. Instruments had to be simple to operate so that high school students could master their use without devoting extensive time to training. Instrument vans (2–5) seemed impractical in Kansas, where some participating schools were as much as 300 miles apart. Minimal transportation costs required small, light-weight instruments that could be mailed. In order for the sharing project to continue after the initial funding expired, an annual service fee was required from each participating school to pay for maintenance and replacement of the instruments. These considerations required instrumentation that was relatively inexpensive and rugged. ChemKits were designed to satisfy these constraints. A ChemKit consists of eight student stations. Each is centered around a TI-82 graphing calculator and a Calculator-Based Laboratory System (CBL) interface (Texas Instruments Inc.). Probes (Vernier Software) include a pH electrode, a colorimeter, and a temperature sensor. In addition, a separate set of electrophoresis kits (Science Vision International) is rotated among participating high schools. ChemKits can be shipped by mail to participating high schools for minimal cost. There were also several constraints to the design of teacher training workshops. To be effective, they had to be attractive to high school teachers. Factors such as cost, stipends, and graduate credit had to be considered. Since months might ensue between a training workshop and the first use of ChemKits, workshops had to be long enough for teachers to develop familiarity and expertise with the equipment. Workshops had to incorporate learning strategies that would be effective in high schools. Since teacher preparation
time during the school year is at a premium, workshops had to provide teachers with tested lesson plans tailored to the instrumentation, short high school class time, and limited laboratory facilities. The Project Nearly 100 high school teachers participated in ChemKits workshops at four college campuses during the past three summers. Host colleges were selected on the basis of faculty interest and location at geodemographic centers. Each college was the site of a four-week workshop. Incentives for teacher participation included a no-cost workshop, a stipend and graduate credit for attendance, and use of the ChemKits in the high school classroom. Each ChemKit workshop involved two college chemistry faculty and twenty high school teachers. After introductory exercises with the equipment, participants selected experiment ideas from the literature, modified them for use with ChemKits in a high school lab environment, and thoroughly tested them. Many of the interesting experiments made use of the graphing capabilities of the calculators—for example, constructing calibration curves for colorimetry or monitoring temperature or pH with time. Some examples of experiments are presented in Table 1. Cooperative learning strategies that allow high school students to share equipment effectively were modeled during the workshops. By the end of the workshop every participant had acquired experience with several experiments. During the school year each college acts much like a lending library to participating high schools, providing technical assistance, performing routine maintenance, replacing equipment as needed, and organizing a sharing schedule. Each Table 1. Sample Experiments Experiment Title
Probe
Iron Content in Food and Water
colorimeter
Kinetics of the Bleaching of Crystal Violet
colorimeter
Enzyme Reactions: Peroxidase from Turnips
colorimeter
Nuts to You: Heat of Combustion
temperature
Heat Loss and Surface Area
temperature
Cooling Curves
temperature
Titration Curves: Mono- and Polyprotic Acids
pH
Soil Leaching and pH
pH
Carbon Dioxide Production and Exercise
pH
Note: Unedited participant experiments are available at cost from David Schubert:
[email protected].
JChemEd.chem.wisc.edu • Vol. 76 No. 10 October 1999 • Journal of Chemical Education
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Chemistry Everyday for Everyone
high school has access to the instruments for about three weeks per year. The cost to participating high schools is $100 per year toward ChemKits maintenance and replacement of equipment and up to $60 per year in mailing costs for the ChemKits. After its initial three-year teacher-training period Project ChemKits is designed to continue indefinitely without external funds.
Table 2. Characteristics of Participating Teachers
Taught chemistry at least 15 years
33
Had taken a college course in analytical chemistry (content)
51
Had modern instrumentation training in last 4 years
30
Conclusions after 3 Years One. Recruitment was one of the most challenging aspects of the project. In spite of multiple statewide mailings to “chemistry teacher”, “science coordinator”, and “principal”, many potential participants indicated that they did not receive the application form. Equipment demonstrations at meetings such as the Kansas Association of Teachers of Science and word of mouth eventually proved to be the best recruiting techniques for workshops. Two. Most participating teachers came to ChemKits workshops with a need for instruction in analytical and instrumental techniques. Most left feeling that this need had been met. (See Tables 2 and 3.) Three. ChemKits workshops increased participants’ knowledge of cooperative learning techniques, but to only a small extent. (See Table 4.) Participants came to the workshops with more experience in these techniques than the planners had expected. Four. Participants need access to ChemKits for three weeks per year for optimal classroom use. Eight fully equipped lab stations in each classroom seems to be a satisfactory number to provide for about three high school students per station. Five. Kansas high school chemistry teachers are often geographically isolated. As a serendipitous bonus, the ChemKits sharing project has reduced this isolation by creating unexpected support networks among high school teachers. Six. Software provided with the equipment and from other sources was more experiment-specific than was desired by ChemKits faculty and participants. One of us (Mitchell) wrote a series of programs with improved generality, user friendliness, accuracy, and ergonomic screen design. These programs are available from the ChemKits Web page at www.bethanylb.edu/chemkits.htm. Seven. Project ChemKits is expected to be operational for many years. Maintenance costs were less than anticipated. During the first three years of operation there were no equipment malfunctions and minimal breakage. Project ChemKits is expected to provide 2000 high school students each year with three weeks of effective hands-on experimentation with laboratory instrumentation. Acknowledgments ChemKits workshops are funded by National Science Foundation grant ESI-9552998. Initial purchase of instrumentation was funded by the Camille and Henry Dreyfus Foundation Special Grant Program in the Chemical Sciences. Thanks to Mark Pomplun, Research Associate at the Center
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Percentage (N = 90)
Teacher Characteristic
Table 3. Survey Measures of Instrumentation Knowledge Instrument
Mean (SD) a Pre-workshop
Post-workshop
CBL interface
0.62 (0.98)
2.89 (0.41)
Graphing calculator
0.93 (1.08)
2.89 (0.41)
pH electrode
1.38 (1.19)
2.85 (0.51)
Colorimeter
0.95 (1.17)
2.86 (0.51)
Temperature sensor
1.07 (1.12)
2.93 (0.33)
aThe rating scale for knowledge of the instrument was 0 (no knowledge of), 1 (have knowledge of), 2 (competent to use), or 3 (plan on integrating into curriculum). For all five survey questions, a t -test indicated that preand post-workshop differences in means were significant at p = .05.
Table 4. Survey Measures of Cooperative Learning Knowledge Topic
Mean (SD) Pre-workshop
a
Post-workshop
Cooperative groups
3.60 (0.95)
4.12 (0.72)
Ability grouping
3.28 (0.93)
3.85 (0.77)
Explaining behaviors
2.94 (0.96)
3.59 (0.82)
Social behaviors
2.98 (1.02)
3.61 (0.83)
Laboratory notebooks
3.29 (0.90)
4.00 (0.76)
Group roles
3.24 (0.92)
4.06 (0.69)
Nature of tasks
3.01 (0.95)
3.97 (0.71)
aThe
rating scale for amount of knowledge of subject was 1(none), 2 (little), 3 (some), 4 (adequate), 5 (a lot). For all seven survey questions, a t -test indicated that pre- and post-workshop differences in means were significant at p = .05.
for Educational Testing and Evaluation, University of Kansas, and ChemKits Evaluator, for help in developing this article. Literature Cited 1. Innovation and Change in the Chemistry Curriculum; National Science Foundation EHR/DUE Rep. No. 94-19; National Science Foundation: Washington, DC, 1994; http://www.nsf.gov/pubs/ stis1993/nsf9419/nsf9419.txt (accessed Jun 1999). 2. Hermans, R., Ed. J. Chem. Educ. 1995, 72, 165–166. 3. Mazzeo, April. J. Chem. Educ. 1995, 72, 195. 4. Craney, C.; Mazzeo, A.; Lord, K. J. Chem. Educ. 1996, 73, 646–650. 5. Newman, A. Anal. Chem. 1990, 62, 449A–450A.
Journal of Chemical Education • Vol. 76 No. 10 October 1999 • JChemEd.chem.wisc.edu
