Let Your Students Teach Themselves Chemistry Procedure for Peer Teaching in Beginning Chemistry Cary Kilner 43 Union St.#3,Portsmouth, NH 03801 High school chemistry is the first rigorous science course for manv students. Some are coenitivelvreadv for it when thev enter the course, while others do not become ready until later in the . vear.. if even then. Besides this. there is alwavs the problem created by the differences in learning ability among students, a problem that results in their acquiring the needed basic information and skills a t different rates and with different degrees of comdeteness. Since much of the chemistrv is necessarily sequential, it becomes difficult to mow along in thecourse if nor allstudents undersland each fundnmentnl at the proper time. (For example, it 1s difficult to teach stoichiometrs or formula writing if not a11 srudents undvritnnd what a mole and an oxidation number are). A second problem arises from the fact that chemistry is often taught along three parallel tracks which are developed simultaneously. These tracks consist of (1)theoretical and conceptual information presented through readings, lectures, and discussions, (2) practical applications acquired in lahoratow activities. and (3) . ..nrohlem-solvineskills taueht throueh " assignments such as balancing equations, reaction predictions, and mathematical computations. Students frequently have difficulty both in acquiring all three kinds of information simultaneouslv and in integrating the various skills and concepts. What is needed to solve both of these ~roblemsis a method of drill, repetition, and application of the learned information so that it can be used in small sequential stew as it is acquired. If the process can also involve action on the part of &dents so that they are doing something with the materials rather than just reading or hearing them, it will be all the more effective. The checksheet method proposed here provides such a vehicle and its use is limited only by the ingenuity and creativity of the teacher to break down into small sequential steps the material to be learned and to desien annrooriate student checksheets. If properly prepared, a checksheet will require students to use theorv. of information. .. to make annlications .. and to carry out mathematical operations so that the three tracks mentioned above can he integrated. Since a checksheet is used by an individual student (with few exceptions) it allows for differential learning rates.
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Checksheets Checksheets are generally given out after an overview of the topic bas been presented in lecture. The checksheets are &itten as perfo&mce objectives in terms that the students can understand, and thev encourage the students to explore topics in more detail. he steps ineluded on the checkiheet are action-oriented requiring the student to do somethinge.g., to read, review, defimkxamine, inspect, demonstrite, explain, write, re-read, or work a problem. The student is instructed to initial an annrooriate blank upon completion of any step. The teacher esgbli&es the order of steos to maximize the effectiveness of the material. ~.and the student is instructed to execute the procedure in sequence. When a articular sten . renuires . interaction with another student, ihe teacher specifies that the step he done with a "twinn-anv available s t u d e n t w h o works with or observes the first student. In such cases the twin is required to initial ~~
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the appropriate steps of the other student's checksheet. At critical steps, where quality control is needed, the teacher specifies that the particular step is to be done with a "student aide." This usually is a fast-working student who has been previously designated and trained hy the teacher. The training of the aide includes checking the student on the specific step, correcting the student where needed, and explaining the rigor required in checking other students. (This also will serve to keep the aides from getting too far ahead of the class since some students who work very efficiently really enjoy the checksheet and can out-distance the rest of the class by two or more days.) The most effective length of a given checksheet is about 20-25 steps (1-1spages). The goal for the fastest students is usually 5-7 school days, with the slowest averaging about 10-11days. (If students lag too far behind, they are expected to come in on outside of class times to work on it.) Some Insights In some steps. the student is reauired to demonstrate a definition or cbncept to a twin. ~erbalizingof a definition is not sufficient for completioh of this step. Instead the student must show or apply the definition by constructing and manipulating specific materials. Materials useful in carrying out these demonstrations are available to the student in small boxes which have been assembled hv the teacher prior to the activity.' Remember also to stress that you or othek do notgive answers to steps on the checksheet. Therefore, your function as a teacher during this time is more as a supervisor than as a source of information. The checksheet can he introduced to the class a t any time. I usually wait 1-2 months until the initial novelty of chemistry wears off and then use the first one to renew their interest, and I use subsequent ones at appropriate intervals to sustain that interest. I have found that too long a checksheet or too frequent use of them will diminish their effectiveness. I have written checksheets on fundamentals, ionic and covalent bonding. the eas laws and the kinetic molecular theow. and solution; ~ h & ewere based on the text t ode; Chemistry" by Metcalf et al. A sample checksheet is presented below. Copies of the other checksheets can be obtained by sending a self-addressed, stamped envelope to the author. Checksheet #I-Ionic Bonding Purpcnr: Toaivr you a basic understandin::
