Discover the Universe in the International Year of Astronomy 2009 (IYA2009)

Are you an astronomy enthusiast? Do you have students who excitedly tell you about what they saw most recently through their own telescope? Then you are probably also aware that the Earth and Space Science content standard for grades 5-8 of the National Science Education Standards has students focusing almost exclusively on the earth to the exclusion of the heavens. Does that mean you cannot exploit your students’ affinity for astronomy in your teaching? Absolutely not! The Science and Technology standard, the Science in Personal and Social Perspectives standard, and the History and Nature of Science standard are all directly related to a study of astronomy.

A recent National Science Foundation (NSF) press release announced the kickoff of the International Year of Astronomy.

IYA 2009 is a global celebration of astronomy and its contribution to society and culture, with strong emphasis on education, public participation and the involvement of young people, and with events at national, regional and global levels. Representatives from more than 135 countries are already involved, forming the world’s largest ever astronomy network.

The article describes several initiatives, underwritten in part by the NSF, occurring in this country and abroad. Two projects in particular may interest you. The first is the Galileoscope project. In this project, several experts designed an easy-to-assemble telescope available to schoolchildren for $10. See the project web site for more details.

The second project, 400 Years of the Telescope, has at least three parts: a documentary, a planetarium program, and an interactive list of over 50 of the world’s largest telescopes. The documentary is the story of the history of astronomy and will air on PBS April 10 at 10:00 P.M. EST. The planetarium program says of its production, which will be available in several formats:

Produced to engage and appeal to audiences of all ages, Two Small Pieces of Glass traces the history of the telescope from Galileo’s modifications to a child’s spyglass—using two small pieces of glass—to the launch of NASA’s Hubble Space Telescope and the future of astronomy. It explores the wonder and discovery made by astronomers through out the last 400 years.

The interactive list of telescopes is laid out in table form, giving the name, location and size of the telescope. The user can click on the name to get an image of the telescope and more details, including its longitude and latitude.

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

Lessons in middle school astronomy can focus on history and society. There may be no other story in the history of science as dramatic as Galileo’s, all because of his “tricked-out” spyglass. Getting students to understand the culture and context of that story is no small feat, but could do wonders to complement a student’s understanding of the nature of science and its relationship with society.

Of course Galileo is not the only astronomer in history. In fact, the pages of the 400 Years of the Telescope web site each feature a color image of one of these astronomers with information regarding their story and contributions to astronomy. Students could work in pairs to research a particular astronomer. Make sure modern-day astronomers are included, rather than limiting the pool to the Renaissance era. The students could then put themselves in chronological order and make a brief oral presentation, complete with visual aids. As they listen, students can be completing a time line template prepared in advance and handed out with the first presentation. Finally, students should reflect on not only the contribution of their particular astronomer, but how that astronomer both affected and was affected by the others, as well as how society responded both then and later. What characteristics of the nature of science can students identify in this study of the history of astronomy?

A more lively approach might be to have students pose as a given astronomer and play some variation of Name that Astronomer or Who Am I?  Your assessment rubric could include attention to how that astronomer was perceived by society, how the astronomer impacted society and the future of science, and any relationships he or she had or has with other astronomers or historical figures.

Here are additional resources from the National Science Digital Library Middle School Portal: Galileo’s Biography; History and Philosophy of Western Astronomy; Telescopes: Our Eyes on the Universe; Light, Optics and Lenses; and Turning Points in Science: Copernican Revolution.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

It’s flu season. Have you been vaccinated? Many of us choose this option because it makes sense to us personally; we prefer to avoid illness wherever possible! Have you had your child between the ages of 6 months and 18 years immunized, as recommended by the Centers for Disease Control (CDC)? That question may cause you to pause.

There are two sides to this coin. In addition to the side representing personal choice, there is the side representing public health. When we all get vaccinated we contribute positively to the public health. The virtual elimination of polio is an excellent example. Beyond the obvious risks of hospitalization and death, influenza causes lost hours at the workplace and in schools and costs everyone in terms of medical expenses leading, in a domino effect, to increased insurance costs among others. Can a balance be struck between personal freedom and public health?

There is a larger discussion around this issue. Like most other states, Ohio requires schoolchildren to be vaccinated against diphtheria, tetanus, pertussis, polio, measles, mumps, rubella, chicken pox, and hepatitis B. As many as 24 states require or are considering requiring all middle school-aged girls to be vaccinated against the human papillomavirus (HPV), one cause of some cervical cancers. And New Jersey is now mandating schoolchildren be vaccinated against the flu. See this NYtimes.com article for more. And this page from the CDC provides comprehensive information regarding vaccinations: http://www.cdc.gov/vaccines/

Parents are inundated with advertisements directing them to have their child immunized against a host of diseases. Where does one draw the line? How many vaccines are too many? Autism is suspected of being caused by some vaccinations administered in infancy. Several studies fail to confirm this hypothesis, but the notion persists among the public. Is that due to low scientific literacy among parents, poor public policy in communicating facts to parents, or deep emotional reactions that no scientific fact can alter? Probably a combination of all three. As classroom teachers, we can use our influence and expertise to help students begin to understand the science so they can make well informed personal decisions and influence public policy later in life.

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

This lesson connects to the Science as Inquiry, Life Science, and Science in Personal and Social Perspectives content standards of the National Science Education Standards. As students grow in their understandings of the nature of science and how science is done, they begin to understand the reliability of science as well as its tentativeness. This understanding allows them to consider the issue of immunizations, personal freedom and public health through the lens of science. At the same time, they must have good working knowledge of the characteristics of living systems, what a vaccine is and what influenza is.

Ask students if they have ever had the flu. How do they know? What did they do about it? Is it something they would like to repeat? Could it have been prevented? Why do we have to get a shot every year? Why isn’t one enough, as it is for other diseases? Be prepared for misconceptions including “the stomach flu.” It’s not necessary to correct students at this point. Have students do some independent research on what a virus is, what influenza is, and what a vaccine is. This could be done in jigsaw groups, or you could provide all students with age-appropriate explanations and visual representations. You might recount to them the real dangers of some flu strains, like the Spanish flu of World War I.

Here are additional resources from the National Science Digital Library Middle School Portal related to influenza and viruses: What’s Making You Sick?; The Big Picture Book of Viruses; How Lou Got the Flu; and PBS Online — American Experience: Influenza 1918

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

Wind power is recognized as a clean, quiet, feasible alternative electricity source around the world. When you think of wind power, what image comes to mind? A wide expanse of undeveloped land dotted with sleek, rotating turbines? What about rooftop turbines right in the city, similar in arrangement to solar rooftop panels?

The NYTimes.com published a story on January 2 about an apartment building in the Bronx with these rooftop turbines. It is predicted they will cut the building’s utility bills for common areas like hallways by one-half each year. According to the figures given in the story, the turbines should pay for themselves in about 11 years.

There are some major differences between this urban setup and the more typical rural environments for wind-generated electricity. First, the rooftop turbines resemble tabletop fans more than the monstrous turbines we have come to associate with wind power. A second difference between this urban setup and the typical rural setup is that the generated power will go directly to the building’s electrical system, not to a central power station first. And the third difference surrounds the quality of wind itself. Urban landscapes create wind blocks and unusual wind currents so not every building is suitable for rooftop turbines. In addition, older buildings may not be able to support the weight of the turbines.

The optimism of this story is encouraging. However, the reality is that it is still quite expensive for the average installation, making wind power out of reach for most of us at this time. Public involvement and a continued creative approach by all stake holders — policymakers, engineers, scientists and consumers — are needed. A New Year’s resolution: learn all you can about alternative sources of energy in your community and communicate with public policymakers to arrive at feasible solutions soon.

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

Wind-generated electricity using rooftop turbines in the city connects to the Science and Technology and Science and Personal and Social Perspectives content standards of the National Science Education Standards. Ask students to describe their perceptions of wind-generated electricity. Do they demonstrate an understanding of the fundamental concept of energy conversion from kinetic to mechanical for example? Do any students mention urban environments? Ask if they believe wind-generated electricity can be done in a city. How? What issues or problems can students predict related to wind power in the urban environment? Are any of those problems insurmountable?

Share the NYtimes.com story with students. Have them identify a list of buildings in their community that might be candidates for rooftop wind turbines. If possible, they can visit the rooftops and take measurements of wind speed and direction. They can do some research into existing incentives available, such as grants or tax exemptions, for organizations that install alternative energy generators. They can contact their local policymakers to either commend them for their efforts if students find them satisfactory; to enquire about why there are not more incentives if that is the case; or to provide suggestions to policymakers regarding how they could provide additional incentives for consumers to go green with rooftop wind generators.

In this way students use their knowledge of energy conversion and technological innovation to influence public policy and culture. They are using skills from across the curriculum, language arts and social studies, in an authentic learning experience.

Here are  additional resources from the National Science Digital Library Middle School Portal related to discussions of energy conversions and wind power: Energy Transfers and Transformations; Introduction to Energy; and Texas Economy Prospers With the Wind.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

Well, it’s the holiday movie season again. And once again, there’s a sci-fi thriller sure to attract students, The Day the Earth Stood Still. This is a remake of a 1951 movie. That plot involved an alien coming to Earth to warn of nuclear war. The remake has climate change as the demise of the planet and still includes the alien. This gives us another opportunity to help students distinguish between science and science fiction.

As educators, we read and hear many stories of how Americans are scientifically illiterate. They may ascribe supernatural explanations to natural occurrences; they may be incapable of applying fundamental science theories to a given situation as a veracity check. Many Americans are unable to make reasonable inferences and logical conclusions from given scientific findings. They may lack the ability to question how data was collected and to consider how methods matter. We complain of mass media contributing to this illiteracy by promoting sensationalized stories as entirely true. In addition, there are stories documenting the actors’ “encounters with” or belief in aliens.

However, a NYTimes.com story reports that moviemakers may be doing a better job of getting the science right. For example, this movie employed a scientist from the SETI (Search for Extraterrestrial Intelligence) Institute as an advisor. The same story also suggests we educators may have a friend in Hollywood, Warren Betts. A Hollywood publicist with a strong interest in science, Betts promoted a recent gathering of California Institute of Technology students, scientists and Keanu Reeves, the movie’s star, to discuss the science and science fiction in the movie. A similar event was held at MIT (Massachusetts Institute of Technology). These meetings allowed students to question the science portrayed in some scenes, and make explicit the distinctions between the science and the science fiction. But what about middle school students — how well equipped are they to discuss the differences?

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

The lesson described connects to the History and Nature of Science, Science as Inquiry and Earth and Space content standards of the National Science Education Standards. Recall an earlier entry made to this blog concerning Indiana Jones movies. You can use a similar approach to this recent movie. Ask what climate change is. Don’t be surprised if students focus solely on global warming. Try to focus on the broader scientific concept of climate change for starters. Ask if they think human activities throughout history could have any impact on climate, or is climate independent of human activity? This link on Climate History from NOAA is useful.

Ask students what science fiction is. Record the characteristics they verbalize. Ask how they think climate change can be, or has been, portrayed in science-fiction movies. Can there be some truth to those portrayals? How can they know?

Here are  additional resources from the National Science Digital Library Middle School Portal related to discussions of climate change and global warming: Exploratorium: Global Climate Change; Global Climate Change: The Ross Ice Shelf; Climate Watch; Antarctica Climate and Data Graphs; and The Little Ice Age Case Study.

I have just returned from the regional conference of the National Science Teachers Association (NSTA) in Cincinnati, Ohio. As usual, I’m filled with inspirational new knowledge regarding science and instructional approaches. I have already created a review activity using my newfound knowledge, not 24 hours post-conference, and I cannot wait to implement it this week!

But there is a rub with attending these conferences, one that I think all science teachers are familiar with. That is the ever-present fact that I cannot keep abreast of the latest scientific findings or make quick and easy decisions about how to use the breakthroughs in age-appropriate, pedagogically sound ways, aligned with standards.

For example, I attended a talk regarding some outcomes of the Human Genome Project. This was the largest scientific endeavor ever attempted in the history of science. Fifteen years later we now know that 98.5 percent of our DNA is “junk” or noncoding; we have about 20,000 genes and 100,000 proteins! How then can we get 100,000 proteins from only 20,000 genes? Enter complexity.

“Noncoding” refers to DNA that does not get translated into a protein. However, this does not mean that it codes for nothing. Got that? It is now known that there are actual genes in the noncoding regions. What? Wouldn’t that make them coding then? No, because they don’t code for proteins, they code for microRNAs. These pieces of RNA are 22 base pairs long and attached to the 3′ end of a gene, and through negative feedback, silence the gene.* Five hundred of these microRNAs have been identified. It turns out that DNA is a blueprint coding not just for proteins but also for gene silencers. Thus, it may be possible to silence a host of disease-causing genes such as the Huntington’s Disease gene. How exciting is that? We have Andrew Fire and Craig Mello to thank for this breakthrough.

But I have not answered the question regarding how we get 100,000 proteins from 20,000 genes.  After transcription, the microRNA, which by the way is now referred to as the transcript, consists of alternating sections of exons and introns. The introns do not contain protein-coding information and are excised. The exons are then spliced together to construct the gene to be translated. However, those exons can be spliced together in various sequences, creating various protein codes. Other species do not have this process, thus they need more genes. This is relevant, worthwhile information, but when, how and how much of it do I present to my students?

NYTimes.com recently published a related article, Scientists and Philosophers Find the ‘Gene’ has a Multitude of Meanings. It seems geneticists are OK with the variation in meaning of terms as this is consistent with the nature of science. As they gain new understandings, conceptual understandings change. So geneticists are fine with using the same terms while they simply modify the associated meaning. But laypeople, including philosophers, propose we use new terms for new conceptual knowledge. For example, “dene” could replace gene, and could capture the concept of noncoding DNA.

I think I prefer the scientists’ perspective: anything to avoid adding new vocabulary to an already bloated scientific vocabulary. With this perspective, I don’t feel obligated to introduce new terminology to my students, so that’s a relief. But I will continue to struggle with keeping abreast of the latest scientific findings as well as what, when and how to present new findings to students. When that struggle ends, I’ll know I’ve retired!

Here are some science education-related resources from the National Science Digital Library Middle School Portal that may assist you in both science content and pedagogical content knowledge: The USGS and Science Education; The Science Education Gateway (SEGway); and Science Education on the Web: Athro, Limited.

*For a more detailed explanation and concise definition of dsRNA see http://www.clontech.com/support/tools.asp?product_tool_id=54329&tool_id=54336. For information regarding “dicer,” the enzyme that enables the gene silencing in concert with the microRNAs See http://www.als.lbl.gov/als/science/sci_archive/120dicer.html.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

What is the International Space Station? How long has it been up there? Who goes up there and for how long? What do astronauts do on the space station? These are intriguing, valid questions you can pose to your students, or perhaps your students have already posed them to you. The NASA space exploration program has a 50-plus year history dotted with some exciting stories, including, but certainly not limited to, Apollo 13. Perhaps it’s the number of “uneventful,” successfully completed missions that should captivate us as much as the creative and suspenseful story of Apollo 13.

The most recent mission performed by the space shuttle Endeavour was scheduled to conclude November 30, 2008. The mission is described as an “extreme home makeover” because the astronauts delivered a number of needed upgrades to the aging space station, which celebrated its 10th anniversary on November 20, 2008. According to a NYTimes.com story, “Endeavour delivered more than eight tons of equipment and supplies to the space station . . . including the water recycling gear, a new toilet, a new galley, a refrigerator and two astronaut sleep stations.” The water recycling gear is intended to provide the means for converting astronaut urine to drinking water. It will be tested for a period of three months before conclusions are made regarding its safety and effectiveness.

Endeavour is also bringing home Gregory E. Chamitoff, who has been living and working on the space station for six months. Doctors anticipate some adjustments will be needed as he re-acclimates himself to Earth’s gravity.

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

One angle teachers could assume with this story is the urine conversion/water recycling idea. This concept connects with earth systems concepts of biogeochemical cycles, and physical science concepts of kinds of matter and changes in matter. Students can review the water cycle and consider how it manifests itself in the closed system of the space station. There are some obviously unique parameters that must be worked with or around. For example, not much evaporation goes on, nor is there much, if any, transpiration from plants. How do those restrictions impact water cycling? If you are feeling brave, you can explore the chemistry of urine. Perhaps it connects to a human body systems study, the excretory system.

The National Science Education Standards Science and Technology Content Standard B states:

• Scientific inquiry and technological design have similarities and differences. Scientists propose explanations for questions about the natural world, and engineers propose solutions relating to human problems, needs, and aspirations. Technological solutions are temporary; technologies exist within nature and so they cannot contravene physical or biological principles; technological solutions have side effects; and technologies cost, carry risks, and provide benefits.
• Many different people in different cultures have made and continue to make contributions to science and technology.
• Science and technology are reciprocal. Science helps drive technology, as it addresses questions that demand more sophisticated instruments and provides principles for better instrumentation and technique. Technology is essential to science, because it provides instruments and techniques that enable observations of objects and phenomena that are otherwise unobservable due to factors such as quantity, distance, location, size, and speed. Technology also provides tools for investigations, inquiry, and analysis.
• Perfectly designed solutions do not exist. All technological solutions have trade-offs, such as safety, cost, efficiency, and appearance. Engineers often build in back-up systems to provide safety. Risk is part of living in a highly technological world. Reducing risk often results in new technology.
• Technological designs have constraints. Some constraints are unavoidable, for example, properties of materials, or effects of weather and friction; other constraints limit choices in the design, for example, environmental protection, human safety, and aesthetics.
• Technological solutions have intended benefits and unintended consequences. Some consequences can be predicted, others cannot.

Help students understand that the International Space Station represents a technological innovation, built through understandings of scientific principles such as Newton’s laws of motion. The station, in turn, provides an environment for a wide range of additional scientific investigations and observations. See http://www.nasa.gov/mission_pages/station/science/index.html for an annotated list of investigations. The fact that the space station is “international” underscores the second bullet point above.

The last three bullets of the standard revolve around issues of pros and cons, risks and benefits, and articulating acceptable levels of imperfection or environmental damage. Students are easily engaged in discussions and organized debates. For example, students can be divided into taxpayers, NASA scientists, NASA engineers, Congress members, and astronauts. The student groups can be presented with a scenario involving a “rescue” mission to the International Space Station, costing X amount of money, involving Y number of astronauts, aborting an important mission testing Z technology or particular scientific investigations. Or they can research what space pollution is and decide what level, if any, is acceptable and why.

Use your imagination and knowledge of your students to come up with additional perspectives related to the International Space Station and concepts in science and technology.

Here are additional related resources from the National Science Digital Library Middle School Portal: Space-Age Living: Building the International Space Station; Boeing Integrated Defense Systems: The International Space Station; and NASA Human Spaceflight.

Image from http://apod.nasa.gov/apod/image/0605/iss2_sts114_big.jpg

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

Well, it’s almost that time again. You can almost see it, smell it, taste it—that perfectly cooked, magnificent bird! How on earth could it ever be a nuisance, and what do trees have to do with anything? After all, their time will come—next month.

Back up. Where did that bird come from? More than likely it came from a place just like the one shown in the photo. As you might imagine, these places generate a fair amount of ammonia, dust and airborne particulate matter. And therein lies the nuisance. According to an article in ScienceDaily, titled Trees Kill Odors And Other Emissions From Poultry Farms, these pollutants are a nuisance to humans living in the surrounding area. As suburban sprawl continues to encroach on rural areas, more people are being exposed to the nuisance.

These pollutants are potentially more than just a nuisance. They can pollute natural running water when they land in it and cause serious respiratory problems for people. But some researchers hypothesized that vegetation could filter much of the odor and particulate matter. They tested their idea, planting a variety of tree types, evergreen and deciduous, glabrous and not, short and tall, around poultry barns.

The ScienceDaily article notes: “In a six-year study, [researchers] found that a three-row plot of trees of various species and sizes reduced total dust by 56 percent, ammonia 53 percent, and odor 18 percent.” Their findings indicated it was most effective to plant either deciduous trees or trees with waxy coatings on leaves closest to the barn, with the other two rows of trees being evergreen. Researchers also point out the potential for energy conservation since these trees provide shade in the summer and a heat-loss barrier in the winter.

A concise and thorough discussion called Interactions Among Urban Trees, Air Pollution and Human Health, from Cornell University, can supplement your background knowledge regarding air pollution and trees.

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

The National Science Education Standards Content Standard F states:

As a result of activities in grades 5-8, all students should develop understanding of

• Personal health
• Populations, resources, and environments

Life Science content standard C says:

As a result of their activities in grades 5-8, all students should develop understanding of

• Regulation and behavior
• Populations and ecosystems

Students can either research or be given information regarding how turkeys and chickens are raised commercially. They should be asked to identify the waste products generated and the impact of a commercial poultry operation on a community. They will encounter stories of the pollution associated with poultry farms, and the confrontations between the poultry farm owners and neighbors.

Then ask students to brainstorm ways to mitigate the pollution using natural, sustainable materials. You may need to drop a few strong hints to lead them to the idea of using vegetation. You can ask, “What if a row of trees was planted around the exterior of the poultry barn? What would that effect?” Students have some idea that trees exchange materials with the environment. “What kind of tree, deciduous or evergreen, would be best and why?”— assuming you live in an area of the country where trees do lose their leaves. Students will see benefits to both, and will perhaps lean to the evergreen. Then ask, “Well, if one row is good, would two or three be even better? What combination of tree types would you choose and why?”

Share the researchers’ findings with students. How do their ideas compare? What questions or ideas for additional research can students generate?

Here are additional related resources from the National Science Digital Library Middle School Portal: The Facts About Ammonia; The Nitrogen Cycle; Measuring Nitrates and Their Effects on Water; and Inside the Human Body: The Respiratory System.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

Sounds like a riddle, but it’s not trivial. We’ll get back to that in a minute. First consider the scenario: The class arrives from physical education. Today’s activity was mat ball, a variation of dodge ball involving lots of kids and lots of contact with balls and mats. They’re pumped, a little sweaty and out of breath, and one or two are a few seconds late—probably not because they were washing their hands! Would you have students wash their hands in this scenario? Not likely. It’s just not part of the lesson plan.

We accept a certain lack of sanitation mostly because it’s not feasible to allow 26-30 kids to wash their hands several times a day. We try to take solace in the hand sanitizers, though rumor has it there’s no substitute for warm water, soap and a minute of scrubbing.

So what’s the big deal? Most bacteria on our skin are harmless or beneficial, right? How many could there be anyway? Well, CBCnews.ca recently published a story, Women lead men in bacteria types, hands down  that might surprise you. Researchers were surprised to find the incredible number of different bacteria species found among 51 college students’ hands and the very low number of species shared by all students. Further, there was a difference between left and right hands. And finally, there was a significant difference between men and women.

According to the news article,

They [researchers] identified 4,742 species of bacteria overall, only five of which were on every hand . . . The average hand harboured 150 species of bacteria. Not only did individuals have few types of bacteria in common, the left and right hands of the same individual shared only about 17 per cent of the same bacteria types . . .

Researchers suspect differences between left-and right-hand bacteria diversity have to do with each hand’s interactions with environment that can alter the hand’s conditions in terms of oil or salinity, for example. Differences between men and women might have to do with hormone production or slight variations in pH. Researchers commented that, for the subjects involved in this study, hand washing did not appear to remove the bacteria. It is important to note the study did not measure mass of bacteria present or population sizes for each species, only the diversity of species present.

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

The National Science Education Standards Content Standard F states:

As a result of activities in grades 5-8, all students should develop understanding of

• Personal health
• Populations, resources, and environments
• Natural hazards
• Risks and benefits
• Science and technology in society

The ideas in this news article connect to the bullets above. The following discussion highlights the ideas in the list.

Ask students if they’ve ever had a bacterial infection. What caused it? What are bacteria? Many will state they are harmful, disease causing germs. How common do they believe bacteria are? Are they in contact with any right now? How do they protect themselves against bacterial disease? Lead students to understand that many kinds of bacteria are harmless and, in fact, beneficial. Our digestion is aided by bacteria, for example. Bacteria are used in the production of yogurt and cottage cheese, among other foods. You can show them photomicrographs indicating bacteria are distinct cells, but quite small. Bacteria impact our personal health in both positive and negative ways.

How are bacteria connected to populations, resources and environments? Remind students that a group of the same kind of bacteria living in the same area is a population. Can a human hand be an adequate environment with resources to support a bacteria population? How many kinds of bacteria do you think might be able to coexist on a single human hand? Entertain all students’ guesses. Share only the numbers from the story with them. How do their guesses compare with the numbers reported?

Try some true or false questions:

1. There is no difference in the kinds of bacteria found on the same person’s right and left hand.

2. Men and women have the same kinds of bacteria on their hands.

3. Among a group of people, there is a high number of different kinds of bacteria that all people share.

Share the rest of the findings reported in the article. Ask students to generate inferences to account for the variation reported. What questions can they generate related to the findings? What kind of tests do they think would be good to conduct next and why?

You can connect the idea of natural hazards to changes in bacteria populations if you care to. After a flood for example, the biggest threat is disease due to polluted water, from overflow of sewage mixing with drinking-water supplies. At times like these, the bacteria populations found on flood-ravaged persons’ hands can be expected to differ from those found under normal conditions.

What are the risks and benefits involved in controlling bacteria through various methods: sanitation, sterilization, irradiation, and antibiotics, for example? What are the risks and benefits of using helpful bacteria to control or minimize the occurrence of harmful bacteria in food?

What role does technology play in public health policies regarding available vaccinations, medicines, and public education campaigns? See the Centers for Disease Control webpage for additional ideas and information at http://www.cdc.gov/ncidod/guidelines/guidelines_topic_bacterial.htm

Here are additional related resources from the National Science Digital Library Middle School Portal: Introduction to Bacteria; A Race of Microorganisms; and The Microbe Zoo.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

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

Caribou 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. For greater detail, this fact sheet from Hinterlands’ Who’s Who is suggested. 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 National Science Digital Library Middle School Portal: Science and the Polar Regions; The Reason for the Seasons; Polar Bears and Climate Change and Animals on the Move

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.

Halloween is approaching and the gore of blood is often a part of the scene. But how about turning your students on to the beauty of blood—the amazing beauty of how it accomplishes all it does?

In middle school, students often investigate the circulatory system and memorize the flow of blood from lungs to heart, to body, back to heart, and finally back to lungs. But how often do they investigate what this “fluid tissue” actually is and how it does all it does for us?

Red blood cells from http://sciencenow.sciencemag.org/feature/science_shots/images/ss_20051027_1.jpg

NYTimes.com recently published an article, The Wonders of Blood, in which blood’s various features are described. For example, the chemistry of blood is likened to sea water, a reference to the evolutionary history of multicellular organisms originating with a single-celled common ancestor living in sea water. Another feature of red blood cells is that they give up their nucleus and DNA in order to carry hemoglobin, the oxygen-binding part of red blood cells. A third feature of red blood cells is their squishing up in order to fit through the tiniest blood vessels in order to reach all 100 trillion or so cells of the human body. Their mantra could be No Cell Left Behind!

Additional features of blood include the three different kinds of blood cells. Besides red blood cells, there are white blood cells and platelets. And, like all other living cells, these cells react to stimuli. When an injury is incurred or an invader detected, these cells are signaled to take action. Another feature of blood is its ability to cleanse the body of things like ammonia. Blood does much more than simply travel through the circulatory system, exchanging oxygen for carbon dioxide.

Students are capable of understanding more than we sometimes challenge them to understand. The role of blood in the body is a perfect opportunity to allow students’ curiosity to take them to deeper understandings.

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. An exploration of blood touches on all three areas, depending on which you wish to emphasize.

Students probably do not conceive of blood as a tissue since it is liquid, not solid. Ask them what the definition of a tissue is — a collection of similar cells organized to perform a coordinated function. Ask them what blood is made of— cells and water. Do these cells work together to perform a function? Does that fit the definition of tissue? Where did we learn that tissues must be solid? You could connect to concepts in matter, such as solids suspended in a liquid, if students have had such discussions already.

Make explicit the overlap and connections from the system level of the circulatory system to the tissue and cellular level of blood. Though we teach students the hierarchical organization of living systems, we may inadvertently communicate that these levels are discrete. Such thinking will prevent students from understanding how the fundamental concept of homeostasis, reacting to stimuli at the cellular level, has important consequences at the system and organismal level.

Concepts in diversity and adaptations can be explored in comparing the blood of various phyla. We should be cautious of using the human system as the standard to which all other systems are compared for their sophistication. Rather, we should get students to think about the niche of the various organisms and how their particular blood works to help organisms accomplish their apparent role in their community and ecosystem. Further, students can think about selection pressures that may have contributed to the evolution of various systems, from the most primitive to the more recently derived.

Here are additional related resources from the National Science Digital Library Middle School Portal : Organ systems: Function, diversity and uniformity; and Sickle vs. Normal Cell; Cellular Service.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? Do you have a favorite activity that you would like to share? We invite you to share with us and other readers by posting your comments. Please check back each week for our newest post or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School Portal science publications. Email us at msp@msteacher.org.