Reading Strategies for Improving Student Work in the Chem Lab John T. Wilson University of lowa, lowa Clty, IA 52242 Irene Chalmers-Neubauer Loyola University, Chicago, IL 6061 1 How often has a chemistrv lab assienment been eiven in -just this way: "Get out your l ~ b m a n uand ~ s read theexperiment on naee 68. Be readv to do the experiment first thine tomorrow." Tomorrow arrives and th;! marathon begins. May the victor get good results! Many students are not prepared t o read a chemistry lab manual let alone be victorious while carrying out an experiment. The structure of the prose and the unfamiliar technical language often limit their comprehension of the new material (1). Finding themselves stumped with little help from the manual, most students turn to each other drawing on their collective exnerience for heln. If this tactic fails. .~~ they ask the teacher. Asalast resort, they reread themanual. In so doine. thev will nrobahlv read it in the same i n a.~.u r o priate waitheydid t6e first time (2). In doing a lab, students read to understand the how, what, and why of an experiment. What is written has little meanine in and of itself until students read it, digest it, think adbut it, and give what is written a personalizid interpretation. This "personalired interpretation" is the basis for action and leainingin the laboratory (3).Students formulating incomplete or inappropriate interpretations may do the wrongthing or not know what to do: Many instructional techniques can be used to help students better organize and interpret written material (4). I t is the purpose of this paper to first examine reading comprehension' as it applies to the chemistry lah and, secondly, to describe techniques that promote better comprehension of lab materials.
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Readlng to Understand Chemistry Students read an experiment for several different purposes. These vary from identifying facts and terminology to understanding complex relational ideas. A single reading technique cannot serve such multiple purposes. Cover-tocover scanning, for example, may provide an overview and general drift, but little about complex sequential processes, such as decidine" how to collect and analvze data. When students perform an experiment, they must read to interpret and seauence a series of urocedures. The validity of what happens (and the results-they obtain) is limited by their functional reading ability (5). The challenge for students and teachers alike is to match the complexity of a task with an appropriate reading strateev. with acloser examination of the content ,Matchine beeins " of a chemistry lab. Content analysis can identify the prerequisite knowledge and thinking necessary for some new idea or behavior to be learned or expressed. Teachers then model,
question, or in some manner cue students to perform the necessary thinking and reading (6). Content is relatively simple to comprehend when only a few steps in thinking are required. For example, naming a compound from its chemical formula may use only singlestep, simple associations. However, comprehension is more complex when the content involves concepts. C o n c e ~ t srequire the recognition of critical attributesbf examples that identify and define the concept. For example, in recognizing several chemical substances as "reactants", students identify properties unique to "reactants", which are its critical attributes, and construct a definition for the concept "reactant". The definition and the process of understanding it help students recognize other substances as reactants or nonreactants. Complex tasks typically require multiple steps in thinking, including the integration of several ideas. These "multiple steps" yield knowledge that is more generalizable than recalled specifics and likely to be applied (transfered) to future tasks. Varying complexities of reading comprehension seem unique enough that four levels can he defined and arranged hierarchically in order of increasing difficulty. These levels, as shown in Figure 1, are (1) literal, (2) inferential, (3) evaluative, and (4) creative (7). The difficulty of a particular level of comprehension is determined by what students have to do to complete the task and not by the written material or the auestions themselves (8,.When faced with performing a \&itication-type lab, students rely heavily on leis complex '.literal" comprehension where laboratory activities are completed in a verbatim manner. When students perform more original "researchtype" activitieh, they read for all levels of cnmprehension,
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The term "reading comprehension" is limited by definition in this paper to the processing of written information using appropriate thinking skills for the determination and understanding of the author's meaning.
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Figure 1. Complexitiesof reading comprehension.
drawing more upon "evaluative" and "creative" levels, as they question and resolve various discrepancies. Each level is defined and described in the section that follows. Also included are lab related questions that can be used bv teachers to differentiate instruction while accommodatingthe varying levels of expected content difficulty. Level 1: Literal Reading The purpose of "literal reading" is to understand the content as written. Initially, reading on this level requires that students retain what was read, a process often achieved only Students then organize hy reading at a slow deliberate and sequence what was read and elaborate it with appropriate hackeround information. As students clarifv the meaning of wcat was presented and make connection"^ within the information. thev should be exoected to put the ideas into their own w&ds,to be sure the; have understood what they have read. Sample laboratory questions answered through "literal reading" are:
What is the most reaaanahle mechansim that explains this chemical change? What facts are most significant? Why? Where would you change the experiment to improve it? How should these chemicals he disposed of? How can you explain these unexpected results? Level 4: Creative Reading The purpose of "creative reading" is to formulate new ideas, going beyond what is presented. Students synthesize and expand ideas from prior analysis into original ideas by contributing their own thoughts to what was read. Creative reading often raises questions and ideas for further consideration. Sample laboratory questions answered through "creative reading" are:
What is another way to analyze the data? What other problem can you see needing resolution? What new way could this product be used? What household products could be substituted for the reagents? Choose another chemical. What could happen if you used it? Make up your own way of doing this. ~
What is the problem or purpose cited in the lab? What chemicals are going to be used? What equipment is needed? What experimental procedure is identified? Identify any special terms and tell what they mean. What aspects of the lah are familiar? List the data (and variables) you will describe. What mass or volume are you to measure? Level 2: Inferential Reeding The ournose of "inferential readine" is to understand the meaning biyond what is literally stated. While initially students develoo a literal meaning, -. thev . now read to applv or deduce elah&ations and connections that are not Gie'ally stated. In this manner, students determine contextual meanings by interpreting the main and related ideas. Analyzing how facts and ideasarerelated is one way students can identify whether relationships are specifically cause-effect, concomitant, or correlated in nature. Students should be expected to support their analysis with a reasoned, datasupported discussion. Sample laboratory questions answered through "inferential reading" are:
What else do you know about the lab that is not given? What concepts relate to this experiment? What other purposes does this experiment serve? What new procedure (not as given) could you fallow? Where should approximate or exact measures be used? What causes the chemical chanee in this reaction? How are the variables related? Level 3: Evaluative Reading The purpose of "evaluative reading" is to judge the efficacy or soundness of one or more meanings derived from what is printed in the manual. This reading process reflects personalized decisions that check the accuracy of ideas or question their validitv. For examole, students mav check oast results and procedures to see whether products are related to the identified chemical theory. The relative value of one procedure over another may also be argued when students question if one or the other should or should not be done. The purposes here are accomplished when students can make reasoned judgments concerning ideas gained from what is presented and provide sound evidence they considered in making these judgments. Sample laboratory questions answered through "evaluative reading" are:
Were your ideas accurate? Which need revising? How valid is the data analysis? Why?
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Methods To Teach Reading wllh Chemistry
Of the many methods described in the literature on reading, the three presented below seem appropriate for chemistry (9). Each method uses distinc~i\.etechniques that help students gain a deeper understanding and greater generalizabilitv of what thev read. Soecificallv. .. these techniaues includk proving interpretation: with references, translating prose into visual "maps" and redirecting student efforts with higher order questions. Research findings have shown2 that some students can increase their comprehension nearly 50% by using more appropriate reading strategies (10). These methods are unlike the all too common outlining and re-reading techniques that seem to limit reading to simple literal level comprehension. Preparation Steps Implementing any one of the three methods that follow requires some advanced preparation by the teacher. Teachers should start by specifying the major purposes for the lab; one or two are enough to provide a sense of direction. Then the teacher should identify the necessary backeround to meet the purposes, namel; terminology,~proce&res, and concepts. This information can become part of the reading assignment or a pre-lab discussion. In the next preparation step, the teacher should divide the lab into seements for silent readiue and studv in class. Short meaningfi segments facilitate theretention-and analysis of oresented information. Teachers then nrenare auestions for kach segment that promote appropriate level ofcomprehension. The previously stated sample questions may be used to help guide the teacher in this process. In describing the following methods, each is identified bv a name to helpremember i t , a major goal, and a brief synopsis of the method. Method 1: Reference Approach
The major goal of the "reference approach" is to help students find the what, how, or why of a lab activity and cite evidence from the reading material that supports their answers. The teacher begins by presenting the general purposes for reading the lab. Then the students are directed to make a quick perusal of an assigned segment, after which they close their manuals. Students recall and discuss major points about the segment, providing reasons that support
A brief synopsis of data and findings from research summarized in this article is available on request.
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the major points. Hence, students might recall the chemicals to he used and discuss some of the possible techniques or reactions that seem a ~ ~ r o o r i a t The e . teacher guides this process through prepl&ed questions and example. After discussion, students read silently to check major points and supporting reasons, refining~themas needed. Then new questions are posed by the teacher, often with a rise in the level of reading comprehension. Such questions are used to shift the focus from broad context to more specific asoects. For examole.. students now mieht elaborate stens " of a procedure, give reasons for a reaction, or summarize an ex~lanation.Students cite sentences from the manual or text to verify their responses. Students are then assigned another s e m e n t and continue the process until the en&e lab is read a i d discussed. Summary and integrative questions can he used to tie the lab to appropriate theory in the text as well as to associate lahoratory procedure with key results and findings.
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Method 2: Mapping
The maior eoal of "ma~oine" .. " is to create a ~ i c t u r ethat illustratesthLinterconnectionswithin the information presented as well as to related information. Translating.. Drose . into a more visual format stresses the sequence and strurtureof ideas. This orocess is characteristic of inferential and evaluative levels of comprehension. Teachers who are uniamiliar with this method will find it h e l ~ f dto work through .a map in advance. The teacher presents the general purpose(s) of the lab and assigns the first segment for study. The students are instructed to read the segment silently, paying special attention to maior " ooints. . such as notine"snecific . chemicals or lab techniques. When nearly all are finished reading (not more than 10 minutes), the students close their manuals and review orally what was read. Major points and procedures are recorded and loosely organized on the hoard. Students check the information for accuracy in their manuals. Then the students and teacher together organize and sequence the information, constructing a map of the reading segment. Preplanned questions help guide students in identifying important interrelationships. A map of the familiar "lime water test for Con" is presented in Figure 2 (11). The map in Figure 2 represents mostly a literal analysis of the activity, emphasizing the sequence of the procedure. A synthesis of data and theory are combined to form a conclusion a t the end of the map. In Fieure 3. the lime water test is analvzed further tocheck for vali&ty "sing evaluative and creative levels of reading. Air is used as a %on-COzn source since the level of COz in air is small enough to he ignored in this test. The validity of the test is extended to testing other sources for COz. With initial maps completed and checked, students begin the lab. As the students cullert data, they refine their map. reflecting their deeper understanding of the experiment. Following the lab, the map can he comhined with data as a means t o help some students interpret and evaluate their findings and produce a written lab report.
& . Results indicate
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Figure 2. Map of the lime water test far COi.
er. Consider, again, the example activity of testing for Con with lime water: Literal: What are the reagents used in the lime water test? Inferential: What reactions happen with these reagents? What is the chemical nature of these reagents? Eualuatiue: What is the validity of these reactions as tests for COz? Creatiue: What household materials are unique sources of COz?
First, the teacher is questioned about the segment by one of the students. Then they reverse roles. The teacher models questions from appropriate comprehension levels. Students take turns asking and answering questions of the teacher. Segment by segment the material is read and questioned until all of the lab material has been studied. Lab begins!
Method 3: Request
The major goal of "Request" is to help students achieve higher levels of comprehension through questioning and analysis (12). T o do this, written materials are analyzed through preplanned questions posed by both students and teacher that extend ideas through the levels of comprehension, from literal to creative. The use of teacher preplanned questions, as examples for students, is essential in this method. As in other methods, all students read silently an assigned segment of the lab. Duration varies with group ability, hut should not exceed 10 minutes. Closing their books when finished, students prepare some questions to ask the teach998
Journal of Chemical Education
M,,*Y p'ecipi,af% test far presence Gas Fire Extinguisher PrapmB I
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Figure 3. Analysis of the validity of Me lime water test.
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Students continue to question each other, checking procedures and results. The teacher "visits" working student groups to encourage students to exchange questions and to see that relevant points, such as procedures and results, are
3. In order to promote greater comprehension of content and process, appropriate reading strategies need to be used in the teach-
ing of chemistry.
Reading and Chemistry in Perspective
Reading is an important tool for success in chemistry. The inability to read limits students in completing assignments. students who comprehend the manual inadequately perform experiments and report findings with only literal, fragmented accuracy. In building an effective reading tool, teachers should consider these points in their planning and teaching: 1. Teachers need to he aware of the level of commehension needed
Literature Clted 1. Johnstone, A. H.J. c ~ ~ . E ~ 1984.61, u c . %I. 2. R o t h k ~ ~Ef.. Coke, E. U.J. VerbdLeorning Verbal Behaulor. 1968.5,86.
A.:
3. Rothkopf, E. 2. Roo. Ed. Roa. 1970,40,325. 4. Piekering, M. J.chom. E ~ U C1987.64, 521. 5. Askou, E.N. In &.ding Erpoaitory ~oteriol:om, w.; white, s., ~ d a . A ; -~F~~C: New York, 1982: Chapter 16. 6. KW-, J. J., J~.:K O T ~ M. ~ . I . -validating ~~~~h~~ by student perfor. rnance"; Florida StsteDsmrtrnent of Education: ~ s l l s h a s s ~1913. e, 7. Canner, J. W.;Chalmers-Neuhauor,I.;etai. "GuidesforTsachingSewadmy Students to Read in Subject Areas"; Domtment of Public Instruction, State of lm:~ e s
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