Take Your Class Outdoors for Organic Gardening

It’s warm outside. The sun is shining bright and white cumulus clouds drift in the blue skies. You notice your students’ eyes wandering outside as you are trying to find ways to keep their’ minds engaged in their science class. You are desperately wishing that you could take your students out of doors while also teaching content related to the National Science Education Standards.

Good news! Outdoor projects such as planting and maintaining a garden satisfy all aspects of scientific inquiry by inviting interactive and hands-on exploration. By creating a garden, students will be able to look at how energy moves throughout an ecosystem. Furthermore, such an activity fosters students’ ability to conduct original research by coming up with their own ways to collect data on a wide range of questions. Outdoor projects also allow students to make observations that are both qualitative and quantitative.

In 2009, Michelle Obama and Washington-area school kids planted the White House vegetable garden. Watch a video of First Lady Obama touring the organic vegetable garden and discussing her goal of educating children about healthy eating. Then read the accompanying article by Dan Shapley with your students. Seeing our government take action will help students to see the importance of their own school garden project. You can see more coverage of the White House garden on a Washington City Paper blog, which was recorded on April 8, 2010.

Connecting to Standards

Outdoor projects, such as planting and maintaining an organic garden, align with the following content standards for grades 5-8 from the National Science Education Standards.

Content Standard C: Life Science

Regulation and Behavior

-All organisms must be able to obtain and use resources, grow, reproduce, and maintain stable internal conditions while living in a constantly changing external environment.

Populations and Ecosystems

For ecosystems, the major source of energy is sunlight. Energy entering ecosystems as sunlight is transferred by producers into chemical energy through photosynthesis. That energy then passes from organism to organism in food webs.

Background Information

What is organic gardening?

Organic gardening does not use synthetic fertilizers or pesticides. Organic gardeners choose plants that are suitable to their specific climate and environmental conditions. It is also important to consider the soil, water supply, wildlife, insects, and even people. Organic gardeners try to minimize any resources the garden consumes, replenishing resources with organic matter.

Why should we garden organically?

When you grow vegetables organically, you are not only eating healthier but also creating a sustainable and more balanced ecosystem. Furthermore, obtaining produce from your own garden is often cheaper than buying it from a grocery store.

Organicgardening.com is an online resource that will answer many questions about organic gardening.

Learning Objectives

Creating an organic classroom garden can be a year-long endeavor, which encourages you to go outdoors with your students. By the end of the gardening project, your students will have:

-An understanding of how organisms may interact with one another.

-An understanding of how changes in an organism’s ecosystem/habitat affect its survival.

-An understanding of how an organism can only survive if its needs are met (e.g., food, water, shelter, air).

-An understanding of how all organisms cause changes in their ecosystem and how these changes can be beneficial, neutral, or detrimental.

-An understanding of food chains and food webs (e.g., producers, herbivores, carnivores, omnivores and decomposers).

-An understanding of how natural occurrences and human activity affect the transfer of energy in an ecosystem.

-An understanding of how the number of organisms an ecosystem can support depends on adequate biotic resources and abiotic resources.

-An understanding of how organisms or populations may interact with one another through symbiotic relationships and how some species have become so adapted to each other that neither could survive without the other.

Activity

To get your students thinking about organic gardening and the components that it entails, have students come up with a design for a garden. This can be done online, bringing technology into the classroom. KiddoNet offers an online planner that allows students to design a flower garden. If computers are not available, the activity can be done using an 8.5″ by 11″ sheet of copy paper and crayons.

When students have completed their garden design, ask them to explain it in a think-aloud fashion. Use the following questions as a guide. (If students need help researching, you may want to give students the questions before they come up with their designs.)

– How big will your garden be? Why?

– Will it be located in a sunny or shady environment?

– Is the area warm or cool?

– How much rainfall does the area get?

– Is the area close to water sources? If not, what arrangements will be needed to ensure that the garden survives?

– What is the soil like?

– Is the location hilly or flat?

– How many plants do you plan to have in your garden?

– How many types of plants do you plan on having?

– What should you consider when choosing your plants?

– Are animals allowed to enter the garden?

– If so, what types? Are they important in the survival of the garden?

– Is there any symbiosis or mutualism occurring in the garden?

– What energy cycles do you expect to occur?

– What biotic resources are important to your garden?

– What are the relationships between the abiotic and biotic parts of your garden?

– How could you maximize diversity?

– How would increased diversity lead to an increased energy transfer throughout the garden?

– How would the presence of humans and pets affect the energy within the garden?

The type of garden or outdoor project that you actually engage your students in depends on the age of the students, financial means, and time constraints. You may want to consider applying for grants to finance an organic garden project. You can find a list of grant opportunities at the Middle School Portal/Getting Grants page.

Additional Information

Middle School Portal 2 has many resources about gardening. Try Thinking Green? Grow Your Own! Linking Agriculture, Gardening and Technology. This resource guide provides ideas and resources for integrating science and technology into studies of agriculture and gardening. It provides answers to these questions: What, and how, can students learn from gardening? How can gardening be accomplished in urban or suburban sites? What technologies enable agriculture and home gardening? What are the underlying science principles of these technologies? What is the economic impact of agriculture and home gardening? Some related careers are also highlighted.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org.

This post was originally written by Brittany Wall and published May 27, 2010 in the Connecting News to the National Science Education Standards blog. The post was updated 4/23/12 by Jessica Fries-Gaither.

Crop Failures and Food Riots

In the spring of 2008, many news outlets reported that rice crop failures in East Asia could have been avoided. An infestation of the brown plant hopper is the cause for the crop failure. The science knowledge and biotechnology needed to breed resistant rice plants have been in existence for several years. However, funds were not available to mass produce these rice strains and get them into the hands of rice growers. This is one example of crop failure that, when combined with other agricultural woes, fueled food riots around the world, but especially among the poorest people in the least developed nations.

The New York Times published an article that comprehensively describes how this preventable tragedy happened – World’s Poor Pay Price as Crop Research Is Cut. As with most sociopolitical issues, a combination of circumstances over a long period of time must be considered if one is to accurately account for the current crisis. The article conveys the history of agriculture research, including the Green Revolution of the 1960s and the great advances that emerged then. Ironically that successful movement contributed to the current lack of available funding; as agriculture problems were solved and world food supplies outpaced demand, research money was directed elsewhere.

The article, part of a series on the world’s food production, includes a nice depth and breadth of information concerning agricultural research. Several photos and related links are included.

How to Turn This News Event into an Inquiry-Based, Standards-Related Science Lesson

The issues described in the news article connect to the History and Nature of Science, Life Science, Science and Technology, and Science in Personal and Social Perspectives content standards of the National Science Education Standards. Here, we narrow our focus to the first two standards. However, this topic – world food supplies as related to agriculture and biotechnology – could easily serve as basis for an interdisciplinary unit in the middle grades.

Do any of the students have experience in growing vegetables? Ask students, what are some of the problems gardeners have to deal with in order to maintain their vegetables? What are some ways to deal with those problems? Help students to include the problem of insect pests in the discussion. Is it reasonable to assume that growers of crops on a large scale also have the same or similar problems? Can growers use the same approaches to deal with their problems that the gardener uses? Why or why not?

Ask students if they can identify one food plant, or crop, that is probably the world’s most common source of food. Consider keeping a list of all ideas and then asking the class to think carefully and critically when they answer these questions: What crop could probably be eliminated from the list, compared to the rest of the list? Why do they believe the food they are choosing to eliminate is probably not the world’s top food crop? You will hope that rice remains on the list!

Ask students to imagine that an insect has infested a large part of the world’s most important food crop. Consider putting the students in small groups in which they predict the consequences of an infestation. You might stipulate that they must have a clear prediction with logical justification for each domain: economy, culture, public health, government, military, and education. Next, ask them to articulate one or two questions that science could investigate in the hope of avoiding the consequences their group identified. For example, Which varieties of rice are most insect resistant? What other food crops can be grown in the areas where rice is currently grown? What nutritional substitutes should/could be distributed to areas where rice is in short supply? Students’ questions will vary widely and all are correct, as long as the questions can be subjected to scientific investigation and seem to point toward a solution to the stated problem.

Share with students the New York Times article, showing that such an event – insect infestation of an important crop – actually happened. Show them the pictures at the story’s web site. Inform them that the knowledge and technology necessary to prevent this disaster already exist. Ask students to speculate then on how this could have happened if people already know how to combat it. Lead them to understand the complexity of the history, funding, cultural values, and competition for funding as contributors to the situation. Finally, confirm and affirm the students’ predictions. They may have heard about food riots for example, in Africa and elsewhere. Ask them what direction they think governments and researchers should go next? Why?

As an extension, you could elaborate on the evolution aspect of the story: the way the bug has evolved through natural selection made possible by use of insecticides.

Here are additional resources from the National Science Digital Library Middle School Portal related to gardening, agriculture and natural selection: Thinking Green? Grow Your Own!; What Are Seed Banks and How Do They Work? and Dr. Saul’s Biology in Motion.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org.

This post was originally written by Mary LeFever and published May 21, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/19/12 by Jessica Fries-Gaither.

After 50 Years, Scientists Still Not Sure How DEET Works

DEET (short for N,N-diethyl-meta-toluamide) is the most widely used insect repellent in the world for a very good reason – it works really, really well! Just a quick spray on exposed skin keeps mosquitoes, flies, fleas, chiggers, and ticks away. Developed by scientists at the U.S. Department of Agriculture and patented by the U.S. Army in 1946, millions of people worldwide use DEET to ward off vector-borne diseases. First of all, why would researchers study DEET if it works so well? While DEET is an effective repellent, it doesn’t work against all bugs, it’s corrosive to plastics and there are concerns about its effect on human health.

 

Structural Formula for N, N-diethyl-meta-toluamide (DEET).
Courtesy of Wikipedia – Click on the image for a larger version.

How DEET actually works has puzzled scientists for more than 50 years. Scientists long surmised that DEET masks the smell of the host, or jams or corrupts the insect’s senses, interfering with its ability to locate a host. Mosquitoes and other blood-feeding insects find their hosts by body heat, skin odors, carbon dioxide (breath), or visual stimuli.

Amazingly, within a few months this year, scientists from two different labs have come up with competing explanations of how DEET works. In March of 2008, researchers at Rockefeller University in New York, said that DEET jams odorant receptors in insect nervous systems, in effect masking odors that would ordinarily attract the bugs. According to Dr. Leslie B. Vosshall, a researcher who worked on the project, now that they know that DEET targets OR83b co-receptors, they can quickly screen thousands of other compounds in hope of finding one that is even more effective and has fewer disadvantages.

Are you sure, ask researchers at the University of California, Davis? Mosquitoes flee because of their intense dislike for the smell of the chemical repellent and not because DEET jams their sense of smell. In August 2008, in a paper published in The Proceedings of the National Academy of Sciences, they provide a simpler explanation. Mosquitoes, they say, smell DEET directly and avoid it.

Dr. Vosshall, involved in the earlier study, said that her team stood by its work, and that its findings were based on a variety of experiments. So for now, the jury is still out.

Connecting to the National Science Education Standards

These competing explanations on how DEET works provides a perfect example of one aspect of the nature of science – Scientific Claims are Subject to Peer Review and Replication. Researchers in labs across the world work on answering many of the same questions. The results of their work are published in peer reviewed journals so that researchers around the world can examine their data and logic, identify alternative explanations, and replicate observations and experiments. Peer review is an integral part of genuine scientific enterprise and goes on continuously in all areas of science.

The National Science Education Standards in the History and Nature of Science Content Standard G describes what middle school students should understand about this part of the nature of science, including:

It is normal for scientists to differ with one another about the interpretation of the evidence or theory being considered.

Different scientists might publish conflicting experimental results or might draw different conclusions from the same data.

It is part of scientific inquiry to evaluate the results of scientific investigations, experiments, observations, theoretical models, and the explanations proposed by other scientists.

Although scientists may disagree about explanations of phenomena, about interpretations of data, or about the value of rival theories, they do agree that questioning, response to criticism, and open communication are integral to the process of science.

Additional Resources

Read the entire National Science Education Standards online for free or register to download the free PDF. The content standards are found in Chapter 6.

Science For All Americans Online: The Nature of Science
Science for All Americans consists of a set of recommendations on what understandings and ways of thinking are essential for all citizens in a world shaped by science and technology.

Household Product Database
List of products that contain DEET.

Chemical Technical Summary for Public Health and Public Safety Professionals
The Department of Health and Human Services provides a summary of all medical cases and research done on DEET.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org.

This post was originally written by Kimberly Lightle and published August 26, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/19/12 by Jessica Fries-Gaither.

Building Quake-Resistant Structures in the Classroom

Every day somewhere on our planet, there is an earthquake, but only the destructive ones in populated areas grab our attention. On January 12, 2010, a 7.0 magnitude earthquake hit Haiti. The next day the headline from the British Broadcasting Corporation (BBC) was Haiti Devastated by Massive Earthquake. The article tells how the earthquake, with its epicenter just outside of the country’s capital of Port-au-Prince, affected an estimated three million people.

A few months later, an earthquake with a magnitude of 6.9 occurred in China’s Qinghai Province on April 13, 2010. An early report from the New York Times was headlined Earthquake Kills Dozens in Northwest China. Later reports would reveal that this earthquake left many buildings destroyed, over 2,000 individuals dead, and even more seriously injured. Other notable earthquakes include the 2010 earthquake in Chile and the 2011 earthquake and tsunami that devastated northern Japan.

Seeing and reading about the aftermath of earthquakes can lead students to believe that nothing can be done to prevent or lessen the destruction and injury. To help students gain an appreciation of the technology currently available, it is important to make students aware of the “before earthquake scene.”

Civil engineers study the effects of earthquakes on foundations and soils. Their research often provides evidence that helps them design earthquake resistant structures. The structures are often able to resist loads that are superimposed on them through earthquake shaking. This is because the structures bend and sway with the motion of an earthquake, or are isolated from the movement by sliders. Watch the Science 360 video “Dissecting an Earthquake”  to learn more about the engineers’ work.

Activity

A great way to introduce students to earthquake-resistant buildings is to have them build their own structures. The following lesson takes approximately two to three days for students to complete in the classroom. The lesson brings in many concepts of the History and Nature of Science standard of the National Science Education Standards.

Note: Prior to this activity, students should have learned about plate tectonics, earthquakes, the Mercalli Scale and the Richter Scale.

In this lesson, students are the civil engineers. By building their own structure with toothpicks and marshmallows, students will learn how engineers construct buildings to withstand damage from earthquakes. Students will test their buildings on an earthquake simulation (a pan of gelatin). They will then re-engineer the structure based on its performance.

To introduce the concept of earthquake-resistant buildings, watch this clip of researchers testing a three-story structure.

After watching the video, you should explain to students that they will make models of buildings and conduct an experiment to test how well their structures stand up under the stress of an earthquake.

The materials needed for this lesson are items that you can find in any grocery or convenience store. You will need toothpicks, marshmallows (miniature), gelatin, and paper to sketch drawings on.

Safety Note: Tell students they should never put anything in their mouths in a science lab. The marshmallows and gelatin are not for eating.

Distribute 30 toothpicks and 30 marshmallows to each student. Explain that engineers have limited resources when building structures. Each structure should be at least two toothpick levels high, buildings must contain at least one triangle, and buildings must contain at least one square.

Do not give as many constraints to IEP or ELL students. You may also want to illustrate how to make cubes and triangles using toothpicks and marshmallows. Show them how to break a toothpick approximately in half. Explain to the students that cubes and triangles may be stacked to make towers. The towers can have small or large “footprints” or bases.

When students have built their structures, place the structures on the pans of gelatin and shake the gelatin to simulate an earthquake. Students should take notes about how their building “responds” during an earthquake. While shaking the gelatin, you may want to ask students these questions: What type of waves are being simulated? How do you know this?

After students have tested their structures, in the next class period they should redesign and rebuild them and test them again. Students should focus on the following questions when redesigning their building: What can they do to make it stronger? Did it topple? Should they make the base bigger? Make the structure taller or shorter?

Students can design and rebuild as many times as the class period allows.

Additional Resources and Ideas

Have students pretend that they are engineers for a civil engineering company. Instruct them to create a flyer or write a letter to convince their company to let them design a better building or structure. (Students should also describe the risks of the area and give background information.) For gifted students, have them do this for a building in the area. This will engage the students and make them think critically about something within their community.

Have your students monitor quake activity weekly by checking the list maintained on the U.S. Geological Survey site. This web site lists the latest earthquakes magnitude 5.0 and greater in the world. The web site also provides a link to a map for each quake location.

The Middle School Portal 2 (MSP2) project has a digital library of resources focused on middle school math and science. You can search the MSP2 collection to find many excellent resources. Here are three to get you started:

Plate Tectonics
This publication offers a sampling of activities and animations to support students as they piece together the plate tectonics puzzle. In some activities, students examine different sources of evidence to try to figure out where and how Earth has changed. They will experience those cherished “aha!” moments when natural phenomena start to make sense. Also included in this publication are excellent reading resources to fill the gaps in students’ and teachers’ understanding of plate tectonics.

Observe Video Taken During an Earthquake
These videos were created for middle and high school students and were taken by security cameras during an earthquake near Seattle, Washington. Each clip shows a view of a different location either within or outside a building. Because the quake originated 30-35 miles beneath the earth’s surface, it caused minimal damage despite having a magnitude of 6.8. Time stamps in the lower left corner of each video clip allow students to determine when shaking started and ended at each location. Students are able to use control buttons to play, pause, and move forward and backward through the clips.

Seismic Waves
An instructional tutorial introduces students to seismic waves caused by earthquakes. Students answer questions as they move through the tutorial and investigate how P and S waves travel through layers of the earth. In one activity, students can produce and view wave motion in a chain of particles. A second activity introduces Love and Rayleigh waves. In a third activity, students study P and S waves by activating four seismographs, watching the resulting P and S waves, and answering interactive questions. Five web sites about waves, seismic action, and earthquakes are included.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at msp@msteacher.org.

This post was originally written by Brittany Wall and published June 4, 2010 in the Connecting News to the National Science Education Standards blog. The post was updated 3/6/12 by Jessica Fries-Gaither.