In the Classroom
Keeping a Scientific Notebook: The Lego® Exercise Bradford D. Pendley Department of Chemistry, Rhodes College, 2000 North Parkway, Memphis, TN 38112 Abstract A brief exercise using Lego® blocks is described. The exercise is designed to motivate students to record observations clearly and unambiguously in their laboratory notebooks immediately after they are made. Keywords Laboratory Teaching/Learning Theory/Practice Introductory/High School Chemistry Teaching/Learning Aids Supplementary Materials No supplementary material available.
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Vol. 74 No. 9 September 1997 • Journal of Chemical Education
Abstract
In the Classroom
Keeping a Scientific Notebook: The Lego® Exercise Bradford D. Pendley Department of Chemistry, Rhodes College, 2000 North Parkway, Memphis, TN 38112 Two challenges in the introductory chemistry laboratory are to motivate students to record observations in their laboratory notebooks immediately after they are made and to record observations clearly and unambiguously. A common problem is that students do not always record their observations immediately after they are made, choosing instead to “reconstruct” their observations after leaving lab. The challenge of teaching students to write in a clear and unambiguous manner occurs partly because students already view their writing as clear and unambiguous. To deal with both problems, I have used the following exercise. At the beginning of the first laboratory period, students are told to examine carefully a figure made from 25 Lego® blocks. I use blocks with eight different rectangular sizes and five different colors. Although the figure is not of anything in particular, it is constructed so as to avoid easily recognizable patterns. It is relatively simple in design (e.g., a rectangle with an occasional block protruding perpendicularly from it) with the different colored and sized blocks dispersed randomly throughout. All Lego blocks are easily visible from the exterior of the figure. Students are told that the figure will be discussed later in the laboratory period. After each student has examined the figure for a few minutes, it is put away and the students check into their lab desks. After everyone has checked in, students meet as a group and are asked if they remember the details of how the Lego figure was constructed. A few volunteers are recruited to reconstruct the Lego figure from memory and are supplied with a bag containing 35 Lego blocks. Twenty-five of the blocks are of the same size and color used to construct the original model, while an additional 10 blocks of differ-
ent sizes but the same colors as the other blocks are also added to the bag. After about 20 minutes, the class reconvenes to examine the similarities between the original figure and those constructed by the volunteers. In my experience, students’ constructions do not have many pieces in common with the original figure. Students are surprised that they were unable to reconstruct the original model and realize that their memory is not as reliable as they thought. This gives the instructor an opportunity to ask them how they could feel confident (as in previous chemistry lab courses) accurately reconstructing events that occurred in lab if they couldn’t even reconstruct a simple figure a short while later. They are asked how they might be better able to handle this situation, and they reply “By taking notes.” A new set of volunteers is recruited to study the figure, but this time they are instructed to take detailed notes so that the figure can be reconstructed from their notes. After 20 minutes of taking notes, the volunteers give their notes to other students who are asked to build the figure using the directions given in the notes. Again the students’ figures are compared with the original figure. To date, the best student figure has reproduced about 50% of the original figure. This result gives the instructor an opportunity to discuss the importance of writing clearly and unambiguously. As a result of this exercise, two things have changed in my introductory labs. First, throughout the semester, all students record observations directly in their notebooks immediately after they are made and without being reminded. Second, students are very responsive to comments made on subsequent lab reports regarding their writing clarity and they produce a better written notebook and report.
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