Wednesday, November 18, 2009

Are Science Labs Vanishing from K-12 Classes?

The pressures on science teachers just keep increasing. Authorities have been taking away their labs for years.

High-stakes testing requires time for the test and for preparation. Where does that time come from? Often, it comes from the lab time because labs are inefficient at learning content, the main focus of high-stakes tests.

Safety regulations have increased considerably in recent years. Now, you cannot have mercury in your classroom at all, for example. States and districts have banned experiments considered hazardous, an action that further limits the ability of teachers to provide lab experience to students.

Budget cuts have hit science departments particularly hard. The cost of providing expendibles and maintaining equipment for experiments has forced the removal of many excellent lab experiences from curricula.

Because many science teachers have been asked to teach in unfamiliar areas, they aren't prepared to develop and run effective labs in these areas. As a result, they do fewer labs.

At the same time, authorities are asking science teachers to provide more lab experience for their students. They rightly argue that such experiences, if done well, can help generate enthusiasm for science, help in understanding the nature of science, help improve scientific reasoning skills, and generally improve student outcome in science courses.

I say that these contradictory trends can only be resolved by the innovative use of technology, and I have chosen to work toward that end. My efforts are beginning to bear the fruit of interest from major online schools, large school districts, and important publishers.

Here's a comparison of the different means that people now employ to provide lab experience to high school students. The list includes hands-on experiments, simulations, large online databases, remote robotic experiments, and prerecorded real experiments. I have been working on this last item.

Simulationsfree to midnoneshorthighlownovery large
Online DBsfreemidmid

free to lowmid to highmidhighlownosmall
lowhighshorthighlownovery large

NOS means "Nature of Science"
Design means "opportunity for experimental design"
Range means "range of experiments available"

Clearly, the choices you make for science labs depend on your goals for the labs. If cost is your primary consideration, then you'll minimize the number of hands-on labs you do. For example, you can use free simulations while sacrificing quality and the nature of science.

Remote robotics and large online databases can be used but, due to their small range, can only fill in for a small amount of a typical high school science course at best.

In my opinion, there's really no contest. Trim down the number of hands-on labs by eliminating those that cost too much, take too long, or don't work well to teach an understanding of the nature of science. Replace these labs with prerecorded real experiments. Pay close attention to the four lab integration goals of America's Lab Report. Ideally, increase the number of investigation experiences by adding more prerecorded real experiments. Find a place in your course for one or two ongoing investigation projects each semester. These projects may involve online databases, remote robotics, hands-on work, field trips, and even prerecorded real experiments or some combination.

You can improve the student investigation experience and handle budget shortfalls too.

© 2010 by Paracomp, Inc., U.S.A.
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Tuesday, November 17, 2009

Simulations are Not Science

Simulations, especially animated simulations, are a great learning tool. They can help students visualize and understand difficult concepts in science classes. Interactive animated simulations can engage students with the concepts. However, you must be careful when inserting simulations into science labs, that is, into student scientific investigations.

Simulations in science have a long and highly-reputed history. They're really the output of calculations from a model. Newton used them to help him investigate his ideas about gravity. He even invented new mathematics to aid in his work. Until recently, the work involved in modeling (simulations) was intense and lengthy. Computers have changed all that. In fact, the first computer was used for simulations.

You might say that simulations are a hallowed tool of science, but they aren't science themselves any more than microscopes, telescopes, or spectrophotometers are science. Scientists don't investigate simulations; they investigate the universe and all of its contents. They may make models of their theories and spend considerable time adjusting these models to see how they may fit with real-world data.

Simulations in science education are another matter entirely. The issue of the appropriate roles of simulations in the science classroom has become very important lately due to the lowering costs of computers and the number of new science simulation options being offered to educators. How should one take best advantage of this sudden abundance?

An example may aid in this discussion. Consider projectile motion, one of the earliest and most common science simulations. For the simplest case of a projectile in a vacuum and a uniform gravitational field, there's no problem writing the equations of motion or calculating the projectile path and impact point. The projectile position is a simple function of time and starting parameters such as initial height, angle of launch, launch energy, and projectile mass.

Indeed, the equations are so simple that a student can perform the calculations necessary to determine the projectile path for a given set of parameters in minutes with a hand-held calculator. A beginning student of computer programming can write a program to print tables of the position in a very short time. All that an existing computer simulation does is save time and, if animated, display the projectile motion.

All of these approaches begin with an assumed equation of motion. Should students be working to discover this equation or using it in some other fashion? Are they investigating a mathematical formula or learning about gravity and motion?

An instructor might have students investigate the motion of real projectiles with the goal of elucidating ideas about motion. Then, these ideas could be used to create a mathematical model. The model can be used to generate data to compare with the real data. Error analysis will help to determine whether discrepancies are within the precision of the real experiments or whether the model has flaws that require revision of the original ideas upon which they were based.

This approach uses simulations in an entirely suitable fashion, one parallel with that which scientists use.

On the other hand, an instructor might decide to use an animated simulation of projectile as the object of student investigation. An entire set of questions could be posed for resolution by the process of trying different parameters in the simulated model. The intended object may be science, but the actual investigation is of some equations, and error analysis, etc. do not enter into this activity at all.

Unless this instructor issues a very strong caveat, students may develop a misunderstanding of science when performing this exercise. The equations have unlimited precision, unlike the real world. They also represent an idealization of the real world.

The gravity field is not uniform. The projectiles do not move through a vacuum. Imprecisions exist in the measurements of the parameters. Investigations of the real world will illuminate these issues and help students to understand science. Science courses are not simply about memorizing content. While simulations may help with content, they have to be used very, very carefully in the investigation part of the course or not at all so that they don't interfere with the important learning that should go on here.

Educators should stop using simulations as the objects of investigations and very carefully use them to augment investigations appropriately or not at all.

These statements should not be interpreted as a license for hands-on purists to decry the use of virtual labs in science courses. Hands-on experiments have their own problems and will be the subject of a later blog entry.

Smart Science® education has found one way to thread the path between the science learning benefits of hands-on experiments and the efficiency benefits of virtual labs.
© 2009 by Paracomp, Inc., U.S.A.
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