Home PublicationsL&LIssuesVolume 26 (1998-1999) October (No. 2)

Changes are integral processes of science and can be measured to produce information for a wide variety of investigations. In this article, the author shows how students can use the World Wide Web to gather real data and analyze it to understand and describe the changes that are of interest to earth and space scientists.

The Internet provides a vast network of resources for schools, and for most users it seems like a limitless and living encyclopedia. But it wasn’t designed that way; it was intended to help scientists collaborate remotely. Fortunately for us, the World Wide Web gives schools access to the same high-quality data and computer-analysis tools used by research scientists. Much of this data is brilliantly colored, immediately relevant to students, and automatically updated every few minutes. It is this real-time, up-to-the-minute data that seems most effective at captivating students.

This article describes good data resources now available, briefly describes how to use Internet data and analysis software, and suggests ways to integrate real-time scientific investigations into your classroom instruction.

Curriculum Resources

The National Science Education Standards (National Research Council, 1996) clearly emphasize that science instruction should use unifying themes and concepts. Change is one such theme. Most things in the universe are in the process of changing. Changes are common in the properties of materials, positions of objects, and functions of systems. Changes in nature can vary widely in rate, scale, and pattern.

Scientists consider most patterns of change to be either trends or cycles. Trends are unidirectional changes that can be linear (such as continental drift), exponential (such as population growth), or sequential (such as the metamorphosis of caterpillar to butterfly). Cyclical changes are repetitions such as the phases of the moon and the recurrence of Earth’s seasons.

Mathematics as the Primary Tool

Mathematics is the language used to describe changes in nature, and its use is essential to the measurement process. Using change as a theme naturally integrates the skills and concepts of science and mathematics. Moreover, analyzing such data allows students to experience scientific discovery firsthand.

The Web provides hundreds of resources that are immediately useful in teaching students about patterns of change. These resources come from a wide range of enterprises: government agencies, commercial industries, and colleges and universities. See Table 1 for examples of locations and lesson ideas. 

Preparation

Four basic software tools are useful for analyzing real-time data from the Internet: 

1. Web browsers such as Netscape Navigator and Microsoft Internet Explorer
2. graphics programs such as Paint-Shop Pro and GraphicConverter
3. image-processing software such as NIHImage and Scion Image
4. spreadsheet programs such as Microsoft Excel

Most of these programs are available for free, and some can be purchased on the Web or at software retailers.

Most schools can’t afford individual Internet access for every student. Fortunately, real-time data analysis doesn’t require constant Internet access. Students can have assigned times to go to a connected computer and gather current image or data files, or a teacher can save the data each day before or after the students arrive or leave. Some students might devise ways to make this process more efficient or even automate it. This is what scientists often do.

Before your students start such a project, they may need background information such as how to use a Web browser. They may need to be reminded how to search effectively, how to find computer resources, which resources are appropriate, how to save images, and how to save and print files. Backing off an address, for example, is one great but often overlooked technique. More images and information often can be found by removing the last directory (the words after the slash) in a Web address. For example, a great image of Uranus taken from the Hubble Space Telescope is available at http://oposite.stsci.edu/pubinfo/PR/97/36/content/ 9736aw.gif. Even more images are found by removing the last four directories from the address and looking at http://oposite.stsci.edu/pubinfo/. 

Instructional Notes

All of the principles that identify high-quality, hands-on, and minds-on science education apply to Web-based science investigations. The best projects are relatively unstructured and will most certainly extend beyond the teacher’s immediate scientific background. The opportunity to learn along with students should not be missed. Sometimes, working with real data is a leap of faith, but most teachers who try open-ended science investigations find them incredibly exciting.

As a first step, you’ll find it helpful to provide students with a time line, milestones, and a reasonably well-defined task.

Highly structured projects are best for schools with extremely limited Internet access. They work well for two reasons. First, they describe the number of images to be analyzed and how and when the analysis is to be done. Second, they provide a strict template for completing a final report. When warranted, a teacher can access data and save it to disk or print images for students to analyze at their desks. This is the only option for teachers who use their home Web access or a school’s single connection before the school day begins. Whenever possible, it’s preferable to make students responsible for gathering their own data on a regular basis, storing it on a floppy disk, using Web resources to gather background information, and immediately analyzing their data on a computer. 

Real-Time Data Analysis. Such data analysis is appropriate for individual students who are working on complex science-fair and multiple-classroom projects. Depending on the students’ ages, they generally need to be introduced to data sources and their interesting attributes. As with science-fair projects, providing springboard project ideas for students is more useful than asking them right off the bat to come up with their own.

One advantage to assigning projects is that a teacher can select interrelated projects for groups of students. For example, one group might monitor changing sunspot activity. The teacher would need to ensure that students could identify a sunspot and access solar images and factual information (current and archived data are available at several Web locations). A second group might monitor the intensity of the northern lights (the aurora borealis). It doesn’t take much data to demonstrate that solar activity often precedes the appearance of the northern lights by approximately three days. Students may do most of the legwork to find resources themselves. It’s not surprising that they’re often better at this than adults. 

The Nuts and Bolts of Data Manipulation

Once a series of images has been obtained over several days or weeks, four powerful procedures can be done with even the smallest computers: (1) trend analysis, (2) animation, (3) enhancement, and (4) measurement. These processes often lead students to investigate more questions or conventional graphing or modeling approaches. 

Trend Analysis. Trend analysis is the most basic form of analysis. Students look for changes in two or more images. Most atmospheric features over the continental United States, for example, move from west to east but at highly varying rates and evolutions. Thus, when looking at real-time U.S. weather maps, students can calculate the rates of change by measuring the number of miles a weather front moves and dividing the rates by the number of hours between images. Geography, map reading, and arithmetic skills are all enhanced by such activities. 

Animation. Animation requires a computer. At the technique’s most basic level, students can stitch together a series of images into an animated GIF using a program such as GifConstruction. Image-processing programs provide more user control. With animations, students can make movies just as good as—and sometimes better than—those on local TV weather reports. The Network Montana Project provides step-by-step instructions on how to use image-processing programs. Some Web sites, such as the Yohkoh Public Outreach Project and The Weather Channel, provide daily data already in movie format. 

Enhancement. Computers also allow students to enhance their data images. By changing the colors they use to display their images, students can make different aspects and features more prominent. Most graphics and image-processing programs allow users to change image colors fairly quickly.

Measurement. Measurement is at the very heart of integrated mathematics and science. Sometimes scales are provided on maps, but students often must indirectly determine an image’s scale. To do this, the student should measure a known distance in centimeters (cm). This distance might be anything: the diameter of a planet or the distance across a continent. The image scale is then calculated as the known distance divided by the ruler distance. To measure any feature in the image, multiply the measured distance in centimeters and the image scale to get the actual size. For example, if a picture of the sun is 15 cm across, then the image scale is the diameter of the sun divided by 15 cm (1,400,000 km/15 cm = 93,333 km per cm). Accordingly, if the size of a sunspot is 1.2 cm, then the actual size of the sunspot is 1.2 cm 3 93,333 km per cm, or 112,000 km.

Similarly, on the computer, any digital image must be calibrated before its features can be measured. For NIHImage or Scion Image, the image must be converted to either the PICT or TIFF format using a graphics program. After the picture is opened, the user draws a line across a known distance (e.g., the map scale, the diameter of a planet, or the distance between two cities). Then the known units followed by the known value are entered so any feature can be measured simply by drawing a line across it. In image-processing software, the scaling holds true no matter how much the user magnifies or enhances the image. 

Assessment

Conducting scientific investigations with real-time data allows many entry points for students with different backgrounds and aptitudes. Students can tackle projects at varying levels of complexity and duration. Accordingly, assessment strategies probably will not be conventional multiple-choice tests that focus on facts. The easiest way to assess student learning is to have students create reports that describe what they did and what they learned. These can be done as written research reports, colorful posters, electronic presentations, or oral reports. Using a checklist, the teacher can evaluate the degree to which students have used appropriate research strategies, the progress students made from their starting points, and the extent to which conclusions are based on the data presented. This is a great opportunity to use a robust combination of performance- and portfolio-assessment techniques. 

Discussion

Some Web sites contain their own animations. This screen shows the J-Track satellite tracking system for monitoring the locations and movement of satellites over the United States (http://liftoff.msfc.nasa.gov/RealTime/ JTrack/Spacecraft.html). Courtesy of Mission Operations Laboratory, Marshall Space Flight Center, NASA

When we think about using Web resources to teach science and patterns of change, we should consider that not all of our classroom students will learn exactly the same list of facts. Scientific data from the Web allows students to explore real scientific data and test real hypotheses in meaningful ways. It encourages students to “do science” rather than simply memorize scientific terms. Knowing scientific vocabulary may be important, but students naturally learn vocabulary in the process of conducting a guided scientific investigation. The goal of increasing the cognitive level of learning science is met by students who actively build their knowledge through motivated investigation.

References

National Research Council. (1996). National science education standards. Washington, DC: National Academy Press. 

Resources

GifConstruction is available at www.pspro.ml.org/wg/animation.html.

GraphicConverter shareware is available at www.lemkesoft.de/.

Microsoft Excel and Internet Explorer are available at educational software retailers or from Microsoft at www.microsoft.com.

Netscape Navigator is available at www.netscape.com.

NIHImage can be downloaded for free from http://rsb.info.nih.gov.

A free trial copy of PaintShop Pro can be downloaded from www.pspro.ml.org.

Scion Image is available at www.scioncorp.com.

Dr. Tim Slater (tslater@physics.montana.edu) is a research assistant professor of physics at Montana State University. Contact him at Montana State University, Department of Physics, Bozeman, MT 59717 USA; 406.994.3560; www.math.montana.edu/~tslater/real-time/.

Copyright © 1998, ISTE (International Society for Technology in Education). All rights reserved.