Saturday, November 15, 2008
Necessary, Not Sufficient
If you have read a few of my posts, you'll note that I feel very strongly that students should have some real science experiences in their science classes. With more and more hands-on labs being pushed aside by virtual labs, I'm concerned about the nature of those labs. If simulations are used as lab substitutes, students lose an imporant opportunity to learn science.
They may learn about science, the vocabulary, laws, and theories of science, but they won't have the opportunity of understand the nature of science.
Nevertheless, simply using real experiments from the material world will not suffice. This fact is the second important conclusion of America's Lab Report (recommended reading). The first important conclusion is that science lab experiences must use the data, objects, and phenomena of the "material world" in their investigations.
What is required in addition to reality? I see two broad areas where additional requirements lie. The first area is in the presentation of the lab units, and the second area concerns how the lab fits into the course.
When preparing for a science lab experience, instructors should allow students to own, at least in part, the work they're about to do. Put the lab into context as solving a problem. Have students do some "research" on the problem. They might talk, read, or do some simple exploratory experiments. Don't just tell them the answer. Allow them to think about it, to mull it over. Then, they'll have some reason to do the lab other than you telling them to.
After the lab is completed, and students have done some analysis, get them together to talk about it. What conclusions have they made? Did all students come to the same conclusions? If not, why not?
In the post-lab post-mortem, you should ask students to identify what they observed directly and what they inferred. Find out how much they think can be inferred from observations. Talk about the quality of data. If possible, talk about data that did not fit expectations and discuss why. Was it experimental error, experimental design, or something else?
What you do before and after a lab can elevate or depress the value of the lab. It can change the lab from a dull, repetitive experience into an exciting investigation.
The second area for making a lab useful in a course requires that you properly integrate the lab into the course. Labs should not take place before a proper learning foundation has been laid. They also should not occur long after the topic has been introduced. Students should see the lab as a natural part of the course flow.
America's Lab Report focuses on four goals for integration.
Science lab experiences must (1) "be designed with clear learning outcomes in mind," (2) "be thoughtfuly sequenced into the flow of classroom instruction," (3) "integrate learning of science content and process," and (4) "incorporate ongoing student reflection and discussion."
Always realize that one of the clear learning outcomes that, according the the NRC, can only come in real lab experience is "understanding the complexity and ambiguity of empirical work." Inasmuch as possible, this should be a learning outcome of every science lab experience because lab time is limited and precious. This goal may not be realized with only a few opportunities to experience it. Don't squander those opportunities on simulations masquerading as science labs. Reserve use of simulations and other visualizations (interactive or not) for non-lab class time.
© 2008 by Paracomp, Inc., U.S.A. www.smartscience.netFollow this author on ETC Journal.