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Teacher Information

The following information will help you use the Web site effectively.

Downloading Graphics

If you have not already preloaded the graphics for the module onto your hard drive, we advise that you do so now. This will make each page display more quickly. Read through the following information, then click on the preload button below.

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How to Use the Module (This section provides information on how to effectively use the module in your classroom.)

This Web site is for middle school science teachers. While some students may find portions of this site useful, the primary audience is classroom teachers and it has been developed with that target audience in mind.

The information and classroom activities found on this Web site were taken from the print versions of LEARN's teaching modules, Cycles of the Earth and Atmosphere: Their Impact on Climate Change and Ozone in our Atmosphere. The on-line module is intended to be flexible allowing the teacher to select some or all of the activities. The sections build on the content and learning of the previous sections yet are not dependent on previous knowledge. Sections and activities may be implemented sequentially or the order may be altered to best fit individual classroom needs.

The on-line module, Cycles of the Earth and Atmosphere, consists of a general overview and seven topical sections each with supporting, field-tested classroom activities designed for middle school grades 6 through 9.

Effort was made to incorporate hands-on experiential learning in each activity. Student outcomes include data generation, recording and analysis, as well as problem-solving, speculating, and decision-making. The activities follow a consistent format that includes the following:

Background Information - These sections, along with the overview information, contain enough information for most teachers to feel comfortable in teaching the activity.

Learning Concepts - The learning concepts provide an overview of the learning purpose behind the activities.

Grade Level and Time - Most of the activities are designed to be used in grades 6 - 9. Recognizing the wide range of student skills and knowledge in these grades, teachers are encouraged to adapt the basic activity to fit their particular classroom needs. We have tried to give realistic time requirements for all aspects of the activity. Our time estimates are meant to be used as a guide.

Alignment to National Standards - Most states have developed science education standards to guide the improvement and accountability of science education. Most of these standards are based at least partially on two documents; The Benchmarks for Science Literacy developed by Project 2061 of the American Association for the Advancement of Science (AAAS) and published in 1993 and The National Science Education Standards developed by the National Academy of Science (NAS) and published in 1996. Both documents present closely aligned sets of standards that should be achieved by students at different grade levels to lead to scientific literacy by the end of high school. Both documents have been very influential in bringing national attention to science education and in shaping the national debate about improving scientific literacy.

Many teachers and curriculum specialists rely on national standards to help them make curriculum design decisions. We support and encourage this activity and are convinced that these standards documents are excellent educational tools for science education. To assist you in using standards, we indicate in each of the activities in these modules which of the NAS standards and AAAS benchmarks are most closely aligned with the learning objectives of the lesson. The document citations refer to text sections and page numbers from the current print editions of the documents.

Both the NAS and AAAS documents are available on-line, or may be ordered from the Web sites below:

AAAS, Project 2061, Benchmarks for Science Literacy:, click on 'Benchmarks on-line' or order in hard-copy.

NAS, National Science Education Standards:, text can be read on-line, downloaded in PDF format, or ordered in hard-copy.

Materials Needed - The activities call for simple, low cost or easy to obtain items readily available to most middle school science teachers. Upper elementary or middle school teachers who do not have access to all of the needed laboratory supplies for a particular activity may want to contact their local high school science department to borrow equipment. For the more complicated activities, teachers may want to recruit high school science students to help them in class.

Procedures - In each activity an attempt was made to both describe the procedure for carrying out the lesson, and to illustrate any product or operations with easy-to-understand graphics.

Assessments - Assessment ideas have been included to assist teachers in determining if their students better understand the activity learning concepts. In some cases, the assessments take the form of further experimentation.

Modifications for Alternative Learners - Teachers know their individual students and their needs far better than anyone else. Some suggestions have been included.

Student Guides - In some of the activities, student guides have been included for ease in implementing the activity in your classroom.

Classroom Safety

The activities described herein are not inherently dangerous, but conducting them improperly or negligently could result in personal or property damage. As a result, the individuals conducting or observing the activity should exercise caution. These individuals should follow instructions closely to facilitate proper execution of the activity. However, instructions are merely guidelines. Individuals must exercise reasonable common sense in executing the activities herein, because even the simplest materials and procedures can be problematic. Following model safety standards for laboratory procedures is a reasonable basis for conducting activities, but does not take the place of using common sense.

Technical Information


The site works best at 1024 x 768 screen resolution (it decreases the amount of scrolling required), although it works fine at 800 x 600.

Browser Compatibility

This site requires a JavaScript-enabled browser. The site has been tested and functions correctly when viewed with Netscape Navigator version 4.7 and Microsoft Internet Explorer version 5.0 or higher. It will probably work on older browsers; you'll have to check to make sure.

Printing Module Pages

To print any page in the module, click on the Print Button in the browser header or select Print from the File Menu.

Copying and Saving Module Graphics

If you want to save a graphic to your computer:


Graphics were designed for a minimum of 16-bit color. This module will not look as intended when running in 256-color mode.

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