Paul Andersen Paul Andersen

Photoelectric Effect

Description:  The photoelectric effect is the emission of electrons when a material is hit with light exceeding a threshold frequency. This provides evidence that light can act as a particle, as well as a wave. Practical applications of this phenomenon include solar cells and image sensors in digital cameras. This demonstration of the photoelectric effect only requires an electroscope, a metal plate and an ultraviolet light.

Web Resource: Photoelectric Effect - Wikipedia

 
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Paul Andersen Paul Andersen

Analog vs. Digital Television

Description:  In this video an analog and a digital television signal are compared. Many students today are not familiar with analog television and the problem of static. Analog television uses changes in the amplitude, frequency or phase of the radio waves to transmit information. Problems of this technology include susceptibility to interference (or static), color consistency, and a smaller image. Digital sends the information as a series of 0's and 1's that are converted into the pixels on the screen. It is difficult to find an analog television signals in the US but the radio is a great substitute.

Web Resource:  Analog vs. Digital Television - Lifewire

 
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Paul Andersen Paul Andersen

The Manhattan Project

Description:  The Manhattan Project was a massive research and development project that included scientists, engineers and the army to create the first nuclear weapon. It required the creation of a massive industrial complex across the country that spent over $2 billion to create bombs that were later used against Japan. Most of the cost of the project went into creating fissile material (material capable of sustaining a nuclear fission chain reaction). This project can be used as an anchoring phenomenon in a unit on nuclear physics and the processes of fission, fusion, and radioactive decay.

Web Resources:  David Hahn - Wikipedia, The Radioactive Boy Scout - Harpers

 
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Paul Andersen Paul Andersen

Felix Baumgartner Space Jump World Record

Description:  In 2012 Felix Baumgartner set the World Record for skydiving from a height of 24 miles. The freefall lasted over four minutes and Felix broke the speed of sound. This phenomenon can be used to introduce the gravitational force being directed down in elementary school. This definition can be expanded upon through middle school and high school to include gravitational fields and application of Newton's Second Law of Motion.

Web Resource:  Red Bull Stratos - Wikipedia

 
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Paul Andersen Paul Andersen

Forced Perspective

Description:  Use the following video from Quirkology to start a unit on Earth's location in space. Freeze the video 7 seconds in and ask the students to rank the following objects from tallest to shortest: painting, man, ball, cup 1, cup 2, and chair.  Then watch the remainder of the video. This can be used to establish the relationship between apparent size and actual size of objects. For example, the moon appears larger than Mars in the sky because it is closer to the Earth.

Web Resource: Forced Perspective - Wikipedia

 
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Paul Andersen Paul Andersen

Amazing Slinky Tricks

Description:  The Slinky was invented by Richard James, an engineer, who was working with springs to support and stabilize equipment on a ship. Simple slinky tricks show how forces (pushes and pulls) change the direction of an object. Students can design a set of stairs, or obstacles, that the Slinky can navigate. In the secondary science classroom it can be used to investigate inertia, oscillations, and Hooke's law. This phenomenon can also be used to investigate wave properties.

Web Resource:  Slinky - Wikipedia

 
 
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Paul Andersen Paul Andersen

Earthships

Description:  An Earthship is a passive solar house that is designed to be off the electrical grid. It is generally constructed with natural and recycled materials. Much of the structure of the house is made with recycled tires that are filled with dirt. Thermal mass from the dirt, solar energy from the Sun, and cross-ventilation are used to keep the temperature within the house in a comfortable zone. This phenomenon can be used study thermal energy transfer, energy conservation, and human sustainability.

Web Resource:  Earthship - Wikipedia

 
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Paul Andersen Paul Andersen

Yellowstone Supervolcano

Description:  Beneath Yellowstone National Park sits a large magma chamber that has erupted three times over the last two million years. Each of these eruptions was classified as an 8 on the Volcanic Explosivity Index (or VEI) making them supervolcanoes. A supervolcano forms when magma below the earth is unable to break through the surface crust and builds up pressure. Thankfully scientists are monitoring this volcano to protect humans from any future eruptions. This could be used as a phenomenon on natural hazards and the technologies that help to mitigate their effects.

Web Resource:  Supervolcano - Wikipedia

 
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Paul Andersen Paul Andersen

Pipehenge: Poor Man’s Stonehenge

Description:  Pipehenge is a daytime astronomy device that can be used to determine patterns in the movement of our Sun and moon.  Pipehenge can be built using plastic pipes so that it is moveable or a permanent "climbable" structure.  According to the makers of this device, students can study astronomy during the day and internalize a model that they can use while observing the night sky.  Secondary students could build a device that could be used with elementary students in the same school district.

Web Resource:  Pipehenge (link currently missing). Still looking for source.

 
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Paul Andersen Paul Andersen

Hemingway’s Polydactyl Cats

Description:  The author Ernest Hemingway was given a six-toed cat that his son named Snow White. His former home in Key West, Florida was turned into a museum and houses nearly 50 cats that are ancestors of this original cat. Cats with extra digits are called polydactyl cats and have inherited a dominant gene. Roughly half of the cats are polydactyl. This phenomenon could be used to study inheritance and variation.

Web Resources:  Hemingway Cats: The Felines That Rule Papa's Key West Estate - Paw Culture, Polydactyl Cats - Wikipedia

 
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Paul Andersen Paul Andersen

Malaria and Sickle Cell Anemia

Description:  Sickle-cell anemia is caused by a single nucleotide mutation in the β-globin gene of red blood cells. This creates incorrectly structured proteins and red blood cells with a characteristic "sickle" shape. This harmful mutation does not affect carriers of the disease. However this mutation can be beneficial in certain areas because it offers protection from malarial infections. This phenomenon can be used in a unit on genetics or evolution.

Web Resources:  The Making of the Fittest: Natural Selection in Humans - HHMI, Sickle-cell Disease - Wikipedia

 
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Paul Andersen Paul Andersen

Shrew Caravan

Description:  Shrews spend most of their lives underground and therefore have very poor eyesight. They rely primarily on their highly developed senses of smell and hearing. When a mother shrew wants to move all of her offspring from one location to another (particularly above ground) each shrew will hold onto the shrew in front forming a long caravan. This could be used as a phenomenon to introduce animal behaviors, especially those of a parent to ensure the safety of their offspring.

Web Resource:  Common Shrew - Wikipedia

 
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Paul Andersen Paul Andersen

Alligators Survive In Ice

Description: As ice covers a lake, the alligators will leave their nostrils out of the water, sometimes frozen in place. Since the alligators are ectothermic (receiving body heat from their environment) they will enter into a state of dormancy called brumation. This amazing phenomenon could be used as an example of successful animal behavior or a form of homeostasis.

Web Resources:  Alligators 'Snorkel' to Survive Ice-Covered Swamp - Live Science, Reptile Brumation - South Carolina Aquarium

 
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Paul Andersen Paul Andersen

Terraforming Mars

Description:  Aside from ethical concerns, turning the planet Mars into a habitable planet would be a scientific challenge. The planet is too cold, lacks a useable atmosphere, and the lack of a magnetic field leaves it susceptible to space weather. Increasing the amount of CO2 in the atmosphere could solves two of these problems through the greenhouse effect. This thought-experiment could provide students an opportunity to better understand interactions between Earth systems.

Web Resource:  Terraforming Mars - Wikipedia

 
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Paul Andersen Paul Andersen

The Dark Snow Project

Description:  The Dark Snow project is a crowd-funded citizen science project to quantify changes in the reflectivity of the ice in Greenland. They are attempting to combine climate change with social media to impact research in the area of albedo-temperature feedback. They have funded two campaigns to study the ice using drones and satellite imagery. The work of this group could allow students to study feedback between Earth systems, discuss climate change, or as a jumpstart for a project of their own.

Web Resources:  Dark Snow Project - Wikipedia, The Dark Snow Project

 
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Paul Andersen Paul Andersen

The Great Oxygenation Event

Description:  The Great Oxygenation Event occurred when cyanobacteria living in the oceans started producing oxygen through photosynthesis. As oxygen built up in the atmosphere anaerobic bacteria were killed leading to the Earth's first mass extinction. The change in diversity and the arrival of appreciable atmospheric oxygen (as evidenced by the red bands in the rocks) can be analyzed to see what happens when a resource that was scarce becomes very abundant.

Web Resource: Great Oxygenation Event - Wikipedia

 
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Paul Andersen Paul Andersen

If We Are What We Eat, Americans Are Corn and Soy

Description:  This CNN story and journal article show how big a role corn plays in the diet of typical Americans. Scientists can do isotope analysis of the carbon to determine the source of carbon. Corn production is heavily subsidized in the US and relies on large amounts of fertilizers and water.

Web Resources:  If we are what we eat, Americans are corn and soy - CNN, Carbon and nitrogen stable isotopes in fast food: Signatures of corn and confinement - PNAS

Public Domain, Link

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Paul Andersen Paul Andersen

Reconstructing Ancient Diets with Isotopes

Description:  Scientists are able to reconstruct the diet of ancient humans by analyzing the isotopes found in their bones and hair. For example by examining the 12C/13C isotope ratio they can determine if the diet was mainly wheat (a C3 plant) or corn (a C4 plant). They can also place the diet in different trophic levels based on the isotopes of carbon as well as nitrogen and oxygen. This phenomenon could start with the following question: Was the paleo diet truly the paleo diet?

Web Resource: Reconstructing Ancient Diets with Isotopes - Wikipedia

 
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Paul Andersen Paul Andersen

Crown Shyness

Description:  In this phenomenon the crowns of certain trees do not touch. The physiological mechanism and cause of this phenomenon is not clearly understood. Since it appears in several species of trees that are not directly related it may be an example of convergent evolution. Students could speculate on why this occurs and in the upper levels may attempt to determine the mechanism of crown shyness.

Web Resource:  Crown shyness - Wikipedia

 
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Paul Andersen Paul Andersen

Why Do Sunflowers Follow the Sun?

Description:  This is an excellent phenomenon that can be used in many different units. According to researchers only young sunflowers will follow the Sun. These flowers are following a natural circadian rhythm to receive the most light for photosynthesis. However when they mature the flowers will mainly face east. The reason for this is fairly simple, bees like warm flowers, and the flowers facing the east are the warmest.

Web Resources:  The Mystery Of Why Sunflowers Turn To Follow The Sun — Solved - NPR, Helianthus - Wikipedia

 
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