Teacher resources and professional development across the curriculum

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Wetlands 1: Marshes and Mud Flats and Bogs, Oh My!

WetlandsIf you live in the Northeast, Midwest, or along the Pacific coast, don’t be surprised if you see small ponds or lakes appear suddenly in your neighborhood during the spring. These are vernal pools – wet areas that form in low-lying zones where water collects in winter and spring. By summer the water evaporates, leaving the site damp or dry through autumn.

Vernal pools are seasonal wetlands, but many other types occur year-round across North America. Wetlands are areas where the soil is always or usually saturated with water, so they support plants and animals that are adapted to moist conditions. Bogs, marshes, mud flats, swamps, and estuaries are all forms of wetlands.

They don’t always look impressive (that’s one reason why many wetlands have been filled in or paved over), but wetlands play important ecological roles. They serve as nurseries and feeding grounds for many types of fish, mammals, and birds; filter pollutants and sediments out of water; and protect coastlines from the impact of storms.

To put wetlands into context, unit 8 of The Habitable Planet describes Earth’s water resources, how they move through the global water cycle, and threats to fresh water. Section 3 shows how the world’s freshwater resources are distributed between ground and surface waters. Section 8 discusses how pollutants–including biological organisms, chemicals, and sediments–impair water quality.

Wetlands can serve as settings for biology, ecology, or chemistry classes. In  Journey North, learn how wetlands are especially important feeding and nesting zones for whooping cranes. Read about what the birds eat, track their migration stops, and discuss how human actions are affecting the wetlands that these birds use. For a biology or chemistry class, see unit 4, section 7 of Rediscovering Biology, “Microbial Diversity,” for a discussion of how archaea break down carbon in swamps. And the interactive on “Garbage – Solutions for Sewage” offers a case study of Arcata, California’s wastewater management system, which includes artificial (constructed) wetlands that improve water quality through physical and chemical processes.

And if you live in a region where vernal pools form, the Association of State Wetland Managers has news, videos, and links to additional materials about these seasonal spring wetlands and the many species that live in them.

Look for post #2 next Wednesday (April 23) with more ideas for teaching about wetlands during American Wetlands Month in May!

Ways to teach about climate change (Part II of II)

HP_surface air increase(See Part I: Why should schools teach about climate change? here.) Teaching about climate change can be daunting: the science is complex, multi-disciplinary, and evolving quickly. But many key ideas about how Earth’s climate system works can be used to illustrate basic ideas in biology, chemistry, and physics.

For example, when biology students study how organisms adapt to their environments, teachers can introduce the idea that climate change is shifting many species’ ranges and altering the timing of seasonal events, such as the first flowering of plants in spring. When students study the carbon cycle in chemistry or earth science, teachers can point out that human activities are adding carbon to the atmosphere, and discuss how Earth’s atmosphere and oceans act as “sinks” for carbon.

What should students know about climate science? The National Oceanic and Atmospheric Administration (NOAA), America’s weather and climate agency, suggests that a climate-literate person:

  • Understands the essential principles of Earth’s climate system,
  • Knows how to assess scientifically credible information about climate,
  • Communicates about climate and climate change in a meaningful way, and
  • Is able to make informed and responsible decisions with regard to actions that may affect climate.

NOAA’s Climate.gov library breaks climate science literacy down into key principles – how energy flows from the sun to Earth, the interactions among Earth’s systems that regulate climate, factors that make climate variable, and the impacts of human actions. The site also offers visuals, videos, experiments demonstrating key concepts, and interactive tools.

Many climate change concepts can be explored through projects, which give students opportunities to apply ideas – and often, to see the impacts of their personal choices. Clarkson University worked with the New York State Energy Research and Development Authority to develop ten project-based climate modules on topics ranging from the greenhouse effect to the climate impact of a “dream vacation.” Lessons target grades 6-8 but can be adapted for other levels.

School groups can also join ongoing citizen science projects across the United States, many of which focus on climate-related events. Three national examples:

  • Journey North, from Annenberg Learner, is a free program that uses observations from students and citizen scientists to track wildlife migration and seasonal change. Teachers can use Journey North to help students learn which indicators of changing seasons are unaffected by climate change (such as the length of daylight at a given time of year) and which are impacted (such as the first arrival of migratory birds in spring).
  • Project Budburst, sponsored by the National Science Foundation, tracks how plant species are responding to local, regional, and national climate changes. Participants submit ongoing or one-time reports on specific plants. The project offers classroom resources for grades K-12.
  • Project FeederWatch, run by the Cornell Laboratory of Ornithology, is a project that surveys bird populations in back yards, parks, and nature centers across North America from November through April. Researchers use the data to track changes in bird species’ winter abundance and distribution.

The Habitable Planet series from Annenberg Learner also provides tools to teach about climate change. The series, presented in videos and an online textbook, explains fundamental environmental science concepts that support an understanding of climate change. Key units include “Atmosphere,” which describes Earth’s energy balance and the role of greenhouse gases in the atmosphere; “Oceans,” which shows the important role that oceans play in absorbing carbon; and “Energy Challenges,” which explains how fossil fuels were created and describes the pros and cons of these and other energy sources. “Earth’s Changing Climate” ties these issues together to show how greenhouse gas emissions from human activities are altering Earth’s energy balance. (Note: for the most current international assessment of climate change science and impacts, see post here from October 30.)

Why should schools teach about climate change? (Part I of II)

EarthAs new findings about global climate change make news, some science teachers are caught between a rock and a hard place. Hundreds of scientists who contributed to the most recent international assessment of climate change science say they are 95 percent certain that human activities are the cause of global warming in recent decades. That’s the same level of confidence experts have that smoking cigarettes causes cancer.

But over the past five years, more than a dozen bills have been introduced at the state level that would allow teachers to present material challenging that scientific consensus. Recent reports* have spotlighted a textbook review panel in Texas, which includes several members who have questioned evolution and climate change science, and is scheduled to vote this month on an approved list of biology textbooks. (Publishers have not altered texts in response to comments from these reviewers.)

The Next Generation Science Standards offer a counterpoint. The standards recommend introducing students to global climate change in middle school as students learn about weather and climate. High school students are expected to learn about using models to understand Earth’s climate system, and to make evidence-based forecasts of the current rate of global climate change and associated impacts.

The high school standards also link global climate change to human sustainability. Students who understand these concepts should be able to explain how human activities are affecting relationships among Earth systems, such as the atmosphere, hydrosphere, and biosphere, and to think critically about solutions that could reduce human impacts on natural systems.

Twenty-six states helped develop the standards, and eight states have already adopted them: California, Kansas, Kentucky, Maryland, Rhode Island, Vermont, Delaware, and Washington. Kentucky’s Gov. Steve Beshear overruled a legislative subcommittee that voted against adopting the standards, which had already been endorsed by the state Department of Education and Board of Education. “My job . . . is to make sure our children are college and career ready when they leave high school. Part of getting them college and career ready is to make sure they study all the different scientific theories [that] are out there that everybody else in the world will be studying,” Beshear said.

By emphasizing critical thinking and investigation, the Next Generation standards are designed to help students understand how scientists develop and test ideas, and to think across disciplines. Climate change is a topic that is well suited to this approach. It draws on multiple fields of science: for example, we need some basic physics to understand atmospheric circulation, while ocean acidification is a chemical process. And scientific understanding of climate science and climate change impacts is evolving in real time today, as researchers test theories and refine models that help us understand past climate shifts and predict what may happen in coming decades.

*Post update: On November 22, 2013, the New York Times published a new piece on the ongoing controversial textbook process in Texas. See the article here.

(Stay tuned next Wednesday, November 20, for Part II: Ways to teach about climate change.)

Climate change: A new global report finds clear human influence (Part I)

(Part I of II updates to The Habitable Planet)

© Greenpeace/Beltra. Polar bears hunt their prey from Arctic sea ice, so climate change threatens their survival.

© Greenpeace/Beltra.
Polar bears hunt their prey from Arctic sea ice, so climate change threatens their survival.

New warming milestones

Late last month, the Intergovernmental Panel on Climate Change (IPCC) released the first volume of its latest report on the state of Earth’s climate. The IPCC, an international scientific body, was created by the United Nations Environment Programme and the World Meteorological Organization in 1988 to advise national governments about climate science and potential impacts from global warming.

The new report finds that Earth’s climate is unequivocally warming, and that it is extremely likely that human activities have been the “dominant cause” of observed warming since the mid-20th century.[1] The IPCC defines “extremely likely” as equivalent to 95 percent certainty. Its last assessment in 2007 called it 90 percent likely that humans had caused observed climate change in recent decades.

As Unit 12 of The Habitable Planet, “Earth’s Changing Climate,” illustrates, Earth is constantly receiving energy from the sun in the form of visible light and radiating some of that energy back into space as heat. Human activities are increasing the concentrations of greenhouse gases, or GHGs (substances that absorb heat) in Earth’s atmosphere, warming the planet’s surface. Since The Habitable Planet was released in 2007, world GHG concentrations have continued to rise, and climate change impacts have become more severe.

One widely-reported milestone occurred in the spring of 2013, when the average concentration of carbon dioxide (CO2) in Earth’s atmosphere reached 400 parts per million (ppm). [2] Carbon dioxide is the main driver of human-induced climate change, and is generated mainly from burning fossil fuels. In the pre-industrial era, atmospheric CO2 concentrations averaged about 280 ppm. In 2005, when the IPCC published its fourth global climate assessment report, they had reached 379 ppm. According to atmospheric scientists, concentrations of 400 ppm probably last occurred several million years ago, when the planet was far warmer than today.[3]

In its new assessment report, the IPCC estimates that if atmospheric concentrations of CO2 reach double the pre-industrial level (a marker the world is on track to reach by mid-century at current rates), global average temperatures would increase by 2.7 to 8.1 degrees Fahrenheit.[4] For comparison, the world warmed by about 1.4 degrees between 1880 and 2012.[5] Some of the most likely impacts of warming include:

  • More intense and frequent extreme precipitation events (rain and snow) in mid-latitudes and tropical regions;
  • Continued melting and thinning of Arctic sea ice and decreasing spring snow cover in the Northern hemisphere; and
  • Faster sea level rise than the changes that have already been observed in recent decades as ice sheets melt and oceans warm, totaling 21 to 38 inches by 2100 if emissions remain high.

Reaching scientific judgments

IPCC reports represent consensus views of hundreds of scientists who review current findings from many disciplines. Working Group I, which produced this volume, focuses on the state of climate science and draws from fields including meteorology, oceanography and ecology. In total, 209 lead authors, 50 review editors from 39 countries contributed to this volume, which cites some 9,200 scientific publications. Reports from Working Group II (on climate change impacts, adaptation, and vulnerability) and Working Group III (on mitigation, or actions to slow climate change) are scheduled to appear in 2014.

IPCC reports are data-heavy and can be challenging to sift through because they consider what will happen under a range of different emissions scenarios. But students can learn about climate change just from seeing how the IPCC approaches its task. Measuring climate change is a scientific challenge, but governments also need to know how impacts such as rising sea levels will affect their countries, and how much difference actions such as shifting away from fossil fuel will make over a given time period. The IPCC’s summary of areas covered by its working groups shows how many specialties have something to contribute to this effort.

The IPCC’s process also illustrates how scientists come to judgments about large-scale problems. Why does the panel review thousands of individual studies to make estimates for these reports? Why does it use multiple scenarios with high, medium and low GHG emissions to project how climate change may progress? Why do the authors assign values such as “virtually certain” and “very likely” to their estimates, as well as numerical probabilities? A look at the IPCC can show students that finding solutions to complex questions like climate change is a slow, iterative process – but one that the world can’t afford to ignore.

Questions for discussion:

  • Which climate change impacts are likely to have major effects where you live? (The IPCC report describes many projected impacts, including sea level rise, changes in amounts and timing of rain and snowfall, and decreasing snowpack in cold regions.)
  • The United States has experienced a number of extreme weather events in the past several years, including Hurricane Sandy in the fall of 2012, record-scale flooding in Colorado’s Front Range earlier this fall, and a multi-year drought across much of Texas. Does evidence suggest that climate change may have contributed to these events? How could climate change amplify a hurricane, rainstorm or drought?

(Look for Part II, “World population: more people, more urban,” on Wednesday, November 6.)

Are you smarter than a Harvard graduate?

privateuniverseHarvardgrad

What causes seasons? Do you think you know? A common answer among school children and college graduates is that seasons are caused by how close the Earth is to the sun, but this answer is not correct. The tilt of the Earth’s axis causes the cycle of the seasons. See an explanation in Science in Focus: Shedding Light, workshop 7.

A Private Universe

More than 23 years ago, video producers asked new Harvard graduates and 9th grade students at a nearby high school some basic science questions, including “What causes seasons?”, and got surprising answers. That footage became A Private Universe, a documentary that looks at how students’ misconceptions block learning. The program looks at celestial movements, the seasons, and how these are taught in school.

In the program, a bright 9th grader named Heather is asked to describe the orbit of the Earth and explain what causes the phases of the moon. Her strange drawing of the orbit leaves her teacher perplexed. Also, Heather is only able to correctly explain the phases of the moon by picking up physical objects and using them to show her thinking. (You can see what became of Heather in the film A Private Universe, 20 Years Later.) Heather’s teacher learned two lessons by observing her explanations: 1. She can’t make assumptions about what students know already. 2. Using manipulatives (like balls to show orbiting planets) is important for understanding scientific concepts.

Where do students’ private theories come from?

Sometimes misconceptions are caused by misleading diagrams and drawings in textbooks that are interpreted or remembered incorrectly. Sometimes the concepts were taught incorrectly. Sometimes students hear words used in one context and apply their understanding to other contexts. Many times, children rely on their experiences, which can limit understanding. Even the brightest students can have trouble with basic concepts, because new ideas are competing with previous knowledge. In addition, teachers are required to cover a lot of material quickly and often don’t have time to tease out these misconceptions.

How can teachers help students?

First figure out what students know about a topic. Anticipate and address any misconceptions that might hinder learning new and related concepts. The three Essential Science for Teachers series include a section called “Children’s Ideas.” Using research on what children believe about basic science concepts, teachers are asked to consider what misconceptions children might have about these concepts and where these ideas might have come from. For example, Earth and Space Science, session 1, considers children’s ideas about soil.

Here is a list of resources from the Essential Science for Teachers series to help you examine children’s ideas in science:

Earth and Space Science

Life Science

Physical Science

Addressing misconceptions is important in all subject areas, not just science. While teaching Spanish at the high school level, I first took for granted that my students understood the parts of speech and learned that many did not. I often hear Africa referred to as a country and that Spanish is the official language of Brazil. Even as adults, we can hold misconceptions somehow learned along the way.

Before you start your next lesson or unit, try to anticipate and address any misconceptions and access prior knowledge. Then build from those ideas while giving students many hands-on opportunities (especially in science and math) to explain their ideas.

What surprising misconceptions have you witnessed in your classes?

 

Expanding Girls’ Horizons in Science & Engineering Month: Astronomer Vera Cooper Rubin Persists

Physics_rubinWhat keeps scientists like Vera Cooper Rubin moving forward when the obstacles in her way are insurmountable by others? Born in 1928, Rubin faced educational limitations set on women during her time: a high school teacher who discouraged her from pursuing science, Princeton’s then policy not to accept women into astronomy programs, and skeptical peers in the science field. But she persisted in her work and gained reputable recognition as an astronomer.

In the 1970s, Rubin and collaborator Kent Ford made a significant discovery in physics. They measured the rotational velocities (how fast they spin) of interstellar matter in orbit around the center of the nearby Andromeda galaxy. Then they compared these studies with those of other galaxies and were able to infer that the galaxies must contain dark matter.

Read how Rubin and Ford arrived at their conclusion and what that meant for understanding dark matter in Physics for the 21st Century, unit 10, section 2, Initial Evidence of Dark Matter. And if you teach students who are curious about science, use Rubin’s story to encourage them to follow their interests. One of them might end up solving the mystery of dark matter altogether.

Writing Activity: Travel the Globe with Latitude Shoes

JN_latitude_shoesCheck out this writing project that’s a fun way to learn about latitude. Kathy Corn recently participated with her students at Mills River, Sugarloaf, and Hillandale Elementary schools in North Carolina.

 

 

 

 

“People everywhere are invited to put on a pair of Latitude Shoes and go for a ride. What would you see if you traveled around the world at your latitude? Write a story about your 24-hour adventure.

  • How fast and how far will you go?
  • Who lives at your latitude?
  • What countries will you visit?
  • What languages will you hear?
  • What seasons do you experience and what clothes do you need?
  • Everyone has the same photoperiod at your latitude, how does the climate compare?”

On the Journey North Web site, the page for this activity includes materials for the full activity; the science, reading and writing, and geography standards connections; a link to share your students’ stories; and a gallery of students’ illustrations and writing. This assignment could be used to assess what students have learned during Journey North’s Mystery Class.

Teaching Newton’s Laws of Motion

GodfreyKneller-IsaacNewton-1689

GodfreyKneller-IsaacNewton-1689

Newton’s laws of motion were written more than 300 years ago and they are still in force.  But how do you teach them so they have impact on students, who often seem inert?

First you must ask yourself the question: Is Newton’s work still relevant in today’s high-tech world? For many years, physicists have been scratching their collective heads about how gravity can exist alongside of the other three forces of nature (electromagnetic, strong nuclear, and weak nuclear forces) because it is many factors weaker than the other forces — the 98-pound weakling at the beach, if you will.

Physicists at the University of Washington’s Eot-Wash lab are testing Newton’s Inverse Square Law at extremely minute distances, less than a hair’s width. In the program “Gravity” from Physics for the 21st Century, you’ll see their experiments and what they have learned. This law defines the force bodies have on each other at various distances. It gives students a glimpse into long-standing physics puzzles and the people working on them.

Students can test their understanding of the 2nd and 3rd laws by observing automobile collisions. You don’t have to go to the street corner and wait for two cars to crash, you can go to Learner.org’s student interactive Amusement Park Physics in the bumper cars section of the virtual park.  The bumper cars provide collisions between moving cars and cars at rest, with drivers of various masses. Students can predict the resulting motion after the collision and perhaps become more aware drivers in the future. (One can always hope.)

Newton’s laws of motion are explained with tabletop demonstrations that use CDs, balloons, eggs, and other common objects in workshop 7 of the Science in Focus: Force and Motion. Advance the video slider to about 29 minutes into the VOD at where you will also learn about how great thinkers from before Aristotle to Newton pondered the questions of the nature of forces and motion acting on objects.

Or you can visit Newton and Galileo in their studies as they work on their theories, in The Mechanical Universe…and Beyond program 6, “Newton’s Laws,” and get a feel for the times of both scientists whose names are synonymous with motion today.

These approaches to teaching Newton’s laws should give your students many ways to think about Newton’s simple and elegant set of rules for all matter.