This is the first of two Science NetLinks lessons in a short series on cells. In this lesson, students compare a plant and animal cell and then make a model of a cell. They select items to represent various cell structures and justify their choices by describing how the items they have chosen represent the actual parts of a cell. Prior to this lesson, students should have at least been introduced to cells, including the basic differences between plant and animal cells. This site provides several links that help to describe and illustrate many aspects that are necessary to build the model. When the students are finished they should understand the basic functions of the structures in the cells. Also, they should be aware of how models are useful and the limitations that exist when using them. (author/kct)

This website gives students and teachers a detailed look at the dissection of a cow's eye through the use of an online video. Teachers can use this as an introduction to the actual dissection of a cow's eye or as an alternative to dissection. It would also be beneficial for use by anatomy teachers or those wishing to investigate various components of the nervous system. For teachers unfamiliar with safety precautions, as well as other dissection-related issues, it would be helpful to read through the NSTA's guidelines for 'Responsible Use of Live Animals and Dissection in the Science Classroom.' in the ORC database.

This website also provides downloadable directions that guide students through the dissection process in a step-by-step format. Labeled diagrams of the eye are also included which should help students locate various parts of the eye during the dissection process.

This content resource aligns with Ohio's Life Science standards for grades 6-8. Real Player is required to view the video. (cb)

This USGS site provides a comprehensive look at the water cycle. The information is conveniently divided into the following topics: Storage in ice and snow, Precipitation, Snowmelt runoff to streams, Infiltration, Ground-water discharge, Ground-water storage, Water storage in oceans, Evaporation, Condensation, Water storage in the atmosphere, Transpiration, Surface runoff, Streamflow, Springs, and Freshwater storage. Each topic includes extensive information and links to additional sources. This content resource could be used by teachers as a source of data and information and for the printable diagram of the water cycle. The entire site could be used by middle grade students studying the water cycle. Additionally students studying physical changes, specifically evaporation and condensation, would find these sections of the resource to be very helpful. (ts)

This content resource features an applet that illustrates the phases of the moon. The user can view the earth-sun-moon system, the moon by itself, or both. This resource would be useful in a lesson or unit on the phases of the moon. It could be used as a demonstration or incorporated into a student individual or group activity. (ts)

This content resource illustrates how tens of billions of tons of carbon move between the atmosphere, hydrosphere, and geosphere each year. The diagram also shows how human activities such as burning fossil fuels and deforestation are contributing to the 5.5 billion tons of carbon dioxide being released into the atmosphere yearly. This resource in not a complete lesson plan, but could be incorporated into a larger unit on the biogeochemical cycles. (author/cb)

Detective Leplant and his partners Bud and Sprout unlock the mysteries of plant life in this content resource. Each of the six cases examines a different aspect of plant life. Each case includes a case brief, facts, mysteries, and activities. The site includes a teacher's guide with suggestions for using the materials in the classroom. Additional background information on plant science is also included for the teacher's reference. This resource could be incorporated into a unit of study on plants. (author/ts)

This lesson is designed to help students construct an understanding of how offspring inherit genes from their parents. Students examine a fictional pedigree and determine which gene is responsible for a given trait. The genetic information for individuals is depicted as a jigsaw puzzle. Terms that students encounter include gene; chromosome; DNA; pedigree; genotype; phenotype; dominant; and recessive. The lesson could follow instruction on meiosis or stand on its own.

A subsection of A Private Universe Project, this resource allows students to investigate the earth-moon system and motion of planetary bodies. Using a journal, teachers gain insight into the students' understanding and the learning process. Students record their predictions, observations, explanations, and questions about the things that puzzle them, and express amazement about the phenomena they witness. Teachers can use the journal as a tool for ascertaining the student's prior knowledge and understanding, identifying any alternative ideas a student might have. Professional and content resources are included, allowing the development of teacher understanding of the concepts.

The objective of this promising practice lesson is to familiarize students with the kinds of things that plants need to grow well. This is the second lesson of a two-part series on where food comes from. These lessons are intended to help students understand that most of the food they eat comes from farms. Students learn how to grow plants and about the kinds of things that promote growth (warmth, sunlight, water, soil). Their activities involve learning about how seeds and plants grow and participating in a simple, in-class gardening project. See ORC # 3462 for the second lesson in the series, "Crops 1: What Where Does Food Come From?"(author/ts)

This informative content resource illustrates the many complex changes that nitrogen goes through during the nitrogen cycle. Nitrogen is continuously circulated throughout the atmosphere, hydrosphere and geosphere. Teachers may find the nitrogen cycle diagram beneficial as it illustrates the conversion of nitrogen from one form to another throughout the cycle. This is not a complete lesson plan, but it could be incorporated into a unit on biogeochemical cycles. (cb)