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.

Human Sense of Smell Is More Sensitive Than You Might Think

ScienceDaily has brought us yet another interesting article related to the National Science Education Standards Life Science Content Standard. My guess is that middle school teachers’ and students’ olfaction capabilities might be a bit superior to the general public’s, given my personal experience in teaching middle school! Nonetheless, scientists from Northwestern University’s School of Medicine report that imperceptible levels of scents affect our judgment in unconscious ways.

The article, Subliminal Smells Bias Perception About A Person’s Likeability, does not explicate the researchers’ questions or hypothesis, but inference indicates their questions were: What concentration levels of scents can people consciously detect? How does scent affect human judgment of the likeability of other humans?

Three scents were used at several levels of concentration, from imperceptible to definitely perceptible. The scents were: “lemon (good), sweat (bad) and ethereal (neutral). . . . Study participants were informed that an odor would be present in 75 percent of the trials.” After participants sniffed a sample, they were shown a photo of a human face with a neutral expression and were asked to rate the person’s likeability along a six-point scale. Though no details are given on how the data was analyzed, the lead author is quoted as saying,

The study suggests that people conscious of the barely noticeable scents were able to discount that sensory information and just evaluate the faces. It only was when smell sneaked in without being noticed that judgments about likeability were biased.

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

Do your students participate in a Science Day competition or activity? Then you know how hard it can be to help students find a topic they can relate to and apply the methods of science. Sharing this article with your students and accompanying it with a discussion of the methods of science used here might just be the perfect bridge to help your students find an accessible topic. Since particular sample sizes and data analysis methods are not described in the article, you and your students could brainstorm a variety of possible approaches.

You could follow up by going through your local library’s electronic periodical data base to find the researchers’ original report in the December 2007 issue of Psychological Science, “Subliminal Smells Can Guide Social Preferences” by Wen Li, Isabel Moallem, Ken A. Paller, and Jay A Gottfried, and sharing with your students the methods these researchers did use. A discussion of the pros and cons of their methods as compared to those brainstormed by your students could round out your lesson.

The ScienceDaily article can also be used as an introduction to a unit on the senses (i.e., structure and function in living things) or on regulation and behavior, both topics within the NSES Life Science Standard. After sharing the article with students, ask: From an adaptive perspective, what value might there be in this phenomenon of imperceptible levels of scent causing unconscious behavior? Are humans the only organism likely to display this trait? How do you know?

Here are some additional resources that are part of the Middle School Portal 2 collection to facilitate your instruction regarding structure and function in living things, olfaction, methods of science, and regulation and behavior: Structure and Function in Living Systems; Enose Is Enose Is Enose; Discovery, Chance and the Scientific Method; Regulation and Behavior.

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 December 13, 2007 in the Connecting News to the National Science Education Standards blog. The post was updated 4/23/12 by Jessica Fries-Gaither.

Seasonal Changes Are Impacted by Climate Change

For us humans, especially in urban settings, the seasons come and go with regularity and cause relatively painless changes in our lives — longer days, shorter days, setting clocks forward or backward as we just did. But for most other animal species seasonal changes do not go unnoticed.  Further, when climate change impacts patterns of seasonal change, animals can be affected.

For example, pregnant caribou depend on particular plants to nourish them while they nurse their calves. The spring calving season is short and the window for peak plant nourishment coincides with that short season. However, these plants are emerging or germinating earlier in the season, in response to warmer temperatures, reaching their peak before calving occurs. Thus, nursing caribou are receiving less nourishment, calves are suffering, and mortality rates are increasing, as reported by ScienceDaily. Researchers believe this is just one example of the impact of climate change that will be documented repeatedly in the near future

caribouCaribou are cued to move to new grazing patches by increasing day length. The plants, however, are cued to emerge or germinate by increasing temperature. This causes a “trophic-mismatch.” If the trend continues, caribou will not survive unless they can find a substitute for their nourishment needs. This may be possible in one of two ways. One is an additional plant species, useful to caribou, becomes established in the ecosystem made possible by the longer growing season. The second way caribou could thrive is if the caribou alter their migration patterns to better align calving with plants at their peak nutrition. Doing so would be a case of the caribou population shifting its      range.

According to a second ScienceDaily article, “One of the main predicted effects of climate change is a forced shift in species’ distribution range.” This comment was made in reference to a plankton scientists have decided was able to change its range to further north in the Atlantic after the last warming trend in climate 18,000 years ago. They attribute this ability to a lot of genetic variability within the species and large populations. This, they say, is good news since it indicates the species can react and adapt appropriately in order to survive and avoid extinction. It is also a cause for optimism since plankton is the base of the food chain.

Conversely then, small, less variable populations are at risk of not adapting to and surviving climate change. What if anything can or should be done?

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

The National Science Education Standards in life science states students should gain understanding in (1) structure and function in living systems, (2) regulation and behavior, and (3) diversity and adaptations of organisms. Climate change affords opportunities to touch on those areas as well as topics in Science and Society, and Earth Science concepts in climate.

Ask students what caribou are, where they live and how they behave. Or direct students to do their own research. This Natureworks site provides a succinct reference for students.  Most will probably know caribou migrate and live in Alaska, but students may not know they also live in Greenland. Many will say caribou are reindeer. Though they are related, they are different. Reindeer are domesticated and live in northern Asia actually.

Students may know caribou migrate, but they may not be fully aware of the adaptations the caribou have, enabling the thousands of miles of migration accomplished each year. Ask students what cues caribou to migrate north in the spring: increasing day length or increasing temperatures? Since temperatures vary, it is adaptive perhaps that caribou respond instead to increasing day length, which is rather constant in its annual pattern.

Now focus on the plants of the tundra. What signals plants it’s time to emerge? Warming temperatures rather than light. After all, an underground root system or a buried seed cannot sense light. To track average temperatures from 1995-2003, students can access Excel files of the data from the Arctic Long Term Ecological Site. In pairs or groups of three, students can find tundra temperature data for a specific year and then share. They can have the program calculate the average temperature each year for the month of June or the first week in June. Graph the data points. What is the pattern?

Tundra plants are low to the ground and small. Caribou have to do a lot of grazing to meet their needs. Turn student attention to the calving and nursing period. Calves nurse for about one month. Nursing caribou need lots of nutrition during that period. What if calves were born one week after plants had reached their maximum? How might this impact the herd over time? Remind students of the two different cues plant and caribou respond to: light and temperature. How might the plant diversity be impacted by a warming trend?

Share the plankton story with students. In sum, two things can happen in response to climate change: adapt or go extinct. Life on the planet survived the last warming trend; thus it may survive this one too. However, human contributions to this warming trend were not present 18,000 years ago. It remains to be seen what difference that makes.

Here are additional related resources from the Middle School Portal 2: Science and the Polar Regions and The Reason for the Seasons.

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 November 5, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/23/12 by Jessica Fries-Gaither.

Mechanism for Antibiotic Resistance Discovered

Those of us born after World War II have take antibiotics for granted. Strep throat? Ear infection? Acne? Bronchitis? Not a problem. Take the full prescribed antibiotic dose and you are cured. The reality of antibiotic resistant bacteria however, disrupts that scenario. No longer can we always trust in a full recovery from a bacterial infection after completing the antibiotic regimen. Rather than continuing to create new and different antibiotics, the trend in research is to discover the mechanisms of antibiotic resistance in order to neutralize it.

How Some Bacteria Survive Antibiotics from ScienceDaily describes how researchers at the University of Illinois, Chicago, studied bacterial action in the presence of erythromycin and related antibiotics. These drugs incapacitate the bacterial protein factories, ribosomes. All cells have ribosomes which are the site of translation in protein synthesis. Erythromycin prevents newly synthesized proteins from detaching from the two subunits of the ribosome, thus preventing the bacteria from thriving. The researchers discovered, however, that these drugs can signal the bacteria to switch a bacterial gene on that enables bacterial release of newly synthesized proteins from the ribosomes. Thus, they effectively resist the drug in a process known as inducible antibiotic expression.

The article quotes one of the researchers

Combining biochemical data with the knowledge of the structure of the ribosome tunnel, we were able to identify some of the key molecular players involved in the induction mechanism. . . .We only researched response to erythromycin-like drugs because the majority of the genetics were already known. There may be other antibiotics and resistance genes in pathogenic bacteria regulated by this same mechanism. This is just the beginning.

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

A manifestation of evolution, antibiotic resistance aligns with the Life Science standard of The National Science Education Standards, “Species acquire many of their unique characteristics through biological adaptation, which involves the selection of naturally occurring variations in populations. Biological adaptations include changes in structures, behaviors, or physiology that enhance survival and reproductive success in a particular environment.” Also related is the structure and function section of the standard: prokaryotic cell structure, the ribosome, and protein synthesis.

Ask students if they have ever had an ear infection or strep throat. What did they do about it? Lead them to disclose that they went to the doctor, were prescribed an antibiotic and took it for the full course, often 10 days. Ask if they were cured then, or did anyone suffer a recurrence within the next week or so? If yes, why? Then what did they do? Lead them to articulate the concept of bacterial resistance. Consider showing visuals of a typical animal eukaryotic cell side by side with a bacterial cell. This will highlight the size and structural difference, and enable student comprehension of how bacterial cells can colonize a eukaryotic cell. Make sure they understand the activity of the millions of bacteria cells a) consumes nutrients needed by one’s own healthy cells and b) produces waste that makes one sick.

If you’ve already discussed the characteristics of living things, cell theory and cell structure, lead students to recall the importance of ribosomes to all living cells. Ask, what might happen if the function of the ribosomes were disrupted? Students should reason that protein production would stop and the cell would die for lack of needed proteins. Inform them that this is the way some antibiotics work; they interfere with the bacterial cells’ ribosome function. (Prokaryotic and eukaryotic ribosome structure varies slightly allowing the eukaryotic ribosomes to remain unaffected.) Ask, what if the presence of the antibiotic signaled the bacteria to produce a protein (turn a gene on) that interfered with the drug’s ability to disrupt the ribosome’s work? Allow plenty of wait time for them to think this through logically. They should arrive at the idea of antibiotic resistance, even if they don’t use that phrase.

Allow students to read the first three paragraphs above and follow the links. The protein synthesis link however, is probably too advanced for middle school students and can be eliminated. Have them read the article How Some Bacteria Survive Antibiotics. Assess: what is an antibiotic? How do drugs like erythromycin work? What is inducible antibiotic expression? How might it be helpful to know the mechanisms by which bacteria resist antibiotics? Describe how antibiotic resistance is an example of evolution.

Here are some additional resources from the Middle School Portal 2 related to antibiotic resistance and bacteria: Introduction to Bacteria; Microbes: Too Smart for Antibiotics?; Microbes: What They do and how Antibiotics Change Them; and What’s making you sick?

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 9, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/23/12 by Jessica Fries-Gaither.

How Is Species Defined and Why Does It Matter? The Politics of Conservation

This post focuses on the definition of species and its implications beyond science content knowledge—specifically, how the definition is related to species conservation and protection.

For example, the brown bear of the Iberian Peninsula is a different species compared with other European brown bears because it is geographically isolated, right? According to a press release, New Study Changes Conditions for Spanish Brown Bears, published by AAAS’s EurekAlert! there are just two small populations of this bear and they are threatened. One idea to help bolster their population size is to introduce brown bears from other European populations. However, this may cause hybridization and eventual loss of the Iberian Peninsula brown bear species. Further, what makes conservation biologists think the two different bears will interbreed successfully?

According to the Life Science content standard of the National Science Education Standards, middle school students should be learning concepts associated with structure and function in living systems; reproduction and heredity; regulation and behavior; populations and ecosystems; diversity and adaptations of organisms. All of these areas of study are related to the concept of species. That is, discussions in any of these areas will necessarily be founded on an understanding of the term “species.”

Can we take for granted that middle school students have developed an accurate concept of species on their own, through personal experience? Because they can distinguish cat from dog, a rose from a maple tree, and a human from an ant, is it safe to assume they have a good grasp of the concept? Not if we wish to facilitate and broaden students’ conceptual understandings to progressively more sophisticated levels.

Students understand that cats and dogs, roses and maple trees, and humans and ants do not interbreed. Thus, they have an understanding of the biological definition of species. But things can get complicated and this definition does not always fit. Another perspective assumes reproductive isolation defines species. That is, if two populations are physically or temporally isolated preventing interbreeding, then they are considered separate species. That works well conceptually for most middle school students’ experience, but what about when individuals from one geographically isolated population are introduced to another, either intentionally or unintentionally, and they successfully interbreed?

When discussions around Mendelian genetics occur, the concept of hybrid is introduced. Plants do this all the time. Is the hybrid a new species? They often can and do interbreed. Are the offspring a new species? Most would hesitate to say yes. Then do we revise our definition of species? Those reproductively isolated populations really are the same species after all?

Contrary to what most people believe, the concept of species seems to be a moving target in terms of pinning a definition on it. As such, it is open to criticism from people who believe science is supposed to be definitive. This presents an opportunity for teachers to reinforce the nature of science, and life science particularly. Living systems, from a single cell to a biome, are dynamic and not entirely definitively understood. (If they were, conservation would probably not be an issue!)

Assuming a fixed definition of species may be unreasonable. One’s definition of species is contextual, dependent upon the current issue under consideration. It is important that discussants have a common definition of species in these instances. Why? Because the focus of and outcomes of species-related discussions can determine political policy, such as what gets listed as a threatened or endangered species and receives federal funding for protection from habitat destruction or hunting.

DNA sequencing allows for almost unequivocal determination of whether individuals from two different populations are the same species, and consequently subject to the same political treatment. In the case of the Spanish brown bears, DNA sequencing suggests they are not a distinct species from other European brown bears. That means introducing bears from other populations will not supplant the Iberian Peninsula brown bears. The proposed conservation strategy is a viable one. Scientists are confident that the introduced bears will successfully interbreed with the Spanish brown bears due to the genetic similarity. This constitutes a prediction, and its accuracy will be determined only after bears are introduced into the area.

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

Consider the American Bald Eagle. It is cited as a success story of the Endangered Species Act (ESA). It has recovered from its endangered status and was delisted in 2007. This means the bird is no longer protected under federal law in terms of some kinds of hunting and habitat protection. States are free to make their own regulations regarding hunting and protection of the species.

More recently, the Northern Rocky Mountain population of gray wolf was delisted. The Western Great Lakes grey wolf population was also delisted. States that are host to these two populations have the power to regulate hunting and management of the animals. However, any wolves on National Park Service land or outside the two areas mentioned above, are under federal government protection.

How is species defined? Ask students if dogs and wolves are separate species. How do they know? Accept all reasonable responses. Are lions and tigers? Are saber toothed cats and Bengal tigers? Lead students to define species in terms of (a) macroscopic anatomy, (b) geographic isolation (lions and tigers), and (c) temporal isolation (extinct and extant cats). This discussion should highlight the difficulty in pinpointing a definition. None is incorrect, yet none is fully sufficient. This is acceptable in classroom discussions, but when conservation groups discuss species, they have to be specific. For example, in delisting the Rocky Mountain gray wolf, the documents specify the geographic region that defines the population. Individual animals falling outside the defined geographic range are not delisted and remain protected by the ESA.

Can students imagine that features other than those immediately visible could be considered in determining who is different and who is the same species? For example, in Batesian mimicry two species are physically similar, but one is poisonous to predators while the other is not. Lead students to understand that there are microscopic or chemical means of determining similarity and differences. Conversely, two populations can appear to be quite different but are chemically quite similar. (This may explain the original assumption that the Spanish brown bear was a separate species from other European brown bears.) The morphological difference is attributed to environmental influences, not genetic differences, and so it is predicted the two populations could interbreed successfully. That’s often good news for conservation management.

What do students think the Endangered Species Act is? Why is it needed? Allow them to brainstorm. Then show them pages from http://www.fws.gov/endangered/about/index.html to either confirm their list or amend it. Can they name any organisms on the list now? Call attention to species other than mammals, including plants. How do students suppose an organism gets listed/delisted? Have students investigate this question at http://www.fws.gov/endangered/species/us-species.html. Facilitate student discovery that the process is not neat and easy necessarily. Rather it can be emotional and partisan. Why?

Here are some additional resources from the Middle School Portal 2 related to conservation and wildlife management: Natural Resources, the Environment, and Ecosystems; and DDT Quest.

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 March 26, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/23/12 by Jessica Fries-Gaither.