Wednesday, March 21, 2012

A Flaw in America's Lab Report

In 2005, the National Research Council published America's Lab Report: Investigations in High School Science (http://books.nap.edu/catalog.php?record_id=11311). This report delivers a scathing indictment of the “typical” lab experience for high school students. It also provides solutions to this sorry situation in the form of a definition for a science laboratory experience, seven goals for the experience, and four integration goals to ensure that science labs fit well into the overall student learning experience. The report covers a great deal of ground including the history of science labs in education.

In discussing science laboratory history in education, the report makes a mistake. This mistake may appear trivial. However, it unveils a serious flaw in how people perceive the history of education. We should not focus only on education errors in the early years but should also examine the successes. There's another problem as well with the following two paragraphs that are taken from pages 19 and 20 of the report.
In these early years, American educators emphasized the theoretical, disciplinary goals of science education in order to prepare graduates for further science education. Because of this emphasis, high schools quickly embraced a detailed list of 40 physics experiments published by Harvard instructor Edwin Hall (Harvard University, 1889). The list outlined the experiments, procedures, and equipment necessary to successfully complete all 40 experiments as a condition of admission to study physics at Harvard. Scientific supply companies began selling complete sets of the required equipment to schools and successful completion of the exercises was soon required for admission to study physics at other colleges and universities (Rudolph, 2005).
At that time, most educators and scientists believed that participating in laboratory experiments would help students learn methods of accurate observation and inductive reasoning. However, the focus on prescribing specific experiments and procedures, illustrated by the embrace of the Harvard list, limited the effectiveness of early laboratory education. In the rush to specify laboratory experiments, procedures, and equipment, little attention had been paid to how students might learn from these experiences. Students were expected to simply absorb the methods of inductive reasoning by carrying out experiments according to prescribed procedures (Rudolph, 2005).

The references are to the following cite: Rudolph, J.L. (2005). Epistemology for the masses: The origins of the “scientific method” in American schools. History of Education Quarterly, 45(2), 341- 376.

It's easy to be arrogant about people's ideas from over 100 years ago. We know so much more now or think that we do. Prof. Hall was the person who discovered the Hall Effect. He developed a series of experiments for students and published them in a pamphlet issued by Harvard University in 1887. The final, revised edition of this pamphlet appeared in 1889 and was superseded by a book, A Text-Book of Physics Largely Experimental (Hall, E. H. and Bergen, J. Y., Henry Holt and Company, New York, 1895) with an original copyright date of 1891. The quotes herein are taken from the 1895 edition.

The number of “exercises” in the book taken from the pamphlet is 46, of which Prof. Hall suggests that any six may be omitted. Numerous additional exercises fill the book, which runs to about 390 pages including appendices and index.

The introduction, addressed “To the Teacher,” describes his approach to teaching physics through experimentation. Extensive quotes from this introduction will demonstrate that Prof. Hall was not so focused on “prescribing specific experiments and procedures” as America's Lab Report (ALR) and, by reference, the Rudolph paper indicate. Instead, they illustrate that Prof. Hall was very concerned with avoiding that path and providing some real opportunities for scientific thinking among the students using his experiments.

The fact of having a list of experiments that might be done has a definite purpose. Prof. Hall writes, “It soon became evident, in view of the inexperience of teachers and the very different standards and methods likely to be adopted by them, that a special course of experiments, carefully thought out and described with much detail, was needed to make the new plan a success.” (Page iii) His problems were associated with the preparatory school teachers, not with the students.

He goes on to explain, “There could be no doubt that, if the course was to be kept from degenerating into mere perfunctory trifling with apparatus, there must be a backbone of quantitative work, ...” Interestingly, given the historical sequence provided by ALR, Prof. Hall chose his experiments based on “practical utility.” He writes, “An attempt was made to bring together such experiments as would have the most frequent and important applications in ordinary life, in the conviction that these would be, on the whole, quite as interesting and important in every other way as any that could be chosen under a different program of selection.” (p. iv)

In the early 1900s, according to ALR, “[Charles] Mann and others attacked the 'dry bones' of the Harvard experiments, calling for a high school physics curriculum with more personal and social relevance to students.” This statement directly contradicts the intent of Prof. Hall as quoted above. Perhaps, the Hall experiments simply, as so many other efforts in education do, became dated in the eyes of some.

Again, according to ALR, “Students were expected to simply absorb the methods of inductive reasoning by carrying out experiments according to prescribed procedures.” Yet, Prof. Hall takes particular pains to avoid this approach.

This book is intended for the use of the student, to enable him to derive the full benefit of his experimental work; to guide him in his thinking, but not to relieve him from the necessity of thinking.” (p. v)

He points out that conclusions to be drawn from experiments by students are deferred somewhat in the book “in order that the student may have an opportunity to frame one for himself; as to numerical results of the various exercises the book gives little or no hint.” (Page v) Finally, on this same page, he puts the lie to the idea that he's produced a cookbook for physics. “Hence the apprehension that some teachers may have, lest the book may give too much assistance to the students, will probably be dissipated upon careful examination. (p. v)
With regard to the detailed nature of some of the experimental directions, Prof. Hall makes the following statement, “The directions given in this pamphlet are in some cases very minute. They are, however, intended to show how the experiments may be done, not how they must be done.” Without detailed directions, some teachers would be lost, whether or not the students were.

He goes on to say, “... the student ... is placed, so far as this is practicable, in the attitude of an investigator seeking for things unforetold. But this attitude, if rigidly maintained, would be likely to keep him for an absurdly long time upon the study of one set of facts, or induce the habit of loose and hasty generalization. ... He should not be told what he is expected to see, but he must usually be told in what direction to look."

In many ways, we see in Prof. Hall quite a modern approach to teaching science. Students work on experiments that connect to “applications in ordinary life.” They are not told the answers but are left to discover them for themselves. Their inquiry is not “open” nor “directed” but is “guided.”

Prof. Hall concludes, “... the main value of the student's inferences, in themselves, is that they will enable him to understand, and without undue stretch of faith to accept, the established conclusions of physicists, and these conclusions should in the end always be made known to him.” (p. xi) He does not prescribe a method for discussing the student inferences. Today, that might be a class discussion in which all students are invited to contribute their inferences, and the teacher guides to the class to talk about the differences and, ultimately, allows for comparison with the current state of the art.

On an earlier page, he provides a summary of his objectives.

The objects to be sought in the course of experimental physics ... may be stated thus: 1st, to train the young student by means of tangible problems requiring him to observe accurately, to attend strictly, and to think clearly; 2d, to give practice in the methods by which physical facts and laws are discovered; 3d, to give practical acquaintance with a considerable number of these facts and laws, with a view to their utility in the thought and action of educated men. (p. vii)

Thus, the conclusion in ALR that, under the Hall approach, “students were expected to simply absorb the methods of inductive reasoning by carrying out experiments according to prescribed procedures” fails under scrutiny of Hall's actual writing.

There's a larger context here as well. ALR uses a secondary source (Rudolph) in place of a primary source (Hall). Scientists all know that such a procedure is dangerous because it puts the filter of the author of the secondary source between us and the actual material. If the secondary source has some particular bias or even simply has limited the scope of the paper, then important, even critical, material may be left out. The preceding discussion shows that, in this particular case, what all scientists know is certainly correct. The ALR authors should have taken the extra time to complete the research rather than relying on a secondary source.

More importantly, the way in which the history is related suggests that the science teachers of old (100+ years ago) didn't know what they were doing. The implication is that although we may learn from their mistakes, they don't have much in the way of positive ideas to offer to 21st century education. Edwin H. Hall is not the only person of his time thinking along the same lines. An important science education writer in England, Frederick W. Westaway, also wrote extensively on teaching science. Others were also active in the pursuit of ways to implement an inquiry-based approach to learning science.

These people were quite successful in graduating students who could think. The reasons for the lack of success of their methods in taking science education by storm is found quite readily. Westaway writes eloquently about the requirements for teachers using his methods, and you'd be hard-pressed to locate any secondary science teacher who could fulfill them today. The requirements include a broad understanding of many areas of science along with deep knowledge of the history of science and thorough comprehension of the philosophy of science.

Hall says, “Not more than half as many pupils at a time can be directed to advantage as can be heard in recitation: perhaps the number twelve is a fair limit.” (p. vi) Where can you find today a class of twelve or fewer science students? How can we expect in today's circumstances to limit every science class's size to twelve?

Hall makes a point that remains germane today. We can remake curricula, set standards, deploy new science labs, train new teachers, retrain current teachers, and make all of the other changes and interventions we'd like. However, we'll never be able to achieve the ideal of oversight for guided inquiry without a breakthrough of some sort. Twelve is not a viable upper limit for class sizes. Few teacher candidates can reach Westaway's ideals for a science teacher in any reasonable number of years.

ALR makes clear that using simulations as lab experiences fail the students miserably. Yet, computer and Internet technology provides our greatest hope for reaching the Hall and Westaway ideal in today's schools. We must find ways to utilize this technology that will work in classes of 30 or so students and that do not require extreme teacher training.

The goal of adequate student science investigation experience for all students in every science class must be realized. As ALR clearly shows, we are failing our students today by not doing our best to reach this goal. We have the means and a road map (ALR). We simply must choose to succeed.

© 2012 by Smart Science Education Inc., U.S.A. www.smartscience.net
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3 comments:

JackFish said...

Good information. I have to remind, however, that one does not "choose to succeed," one must *plan* to succeed. Planning also includes designating resources, assigning personnel and collecting monies to make success a reality.

JackFish said...

Good information. I have to remind, however, that one does not "choose to succeed," one must *plan* to succeed. Planning also includes designating resources, assigning personnel and collecting monies to make success a reality.

Unknown said...

Success is a choice. That choice necessarily involves planning.