Posted by David Wetzel
Heat and Temperature
Students have many misconceptions about science.These misunderstandings are typically held tight by students, because they are commonly misused by parents, siblings, relatives, movies, and their favorite television shows.
Student Misconceptions
Here are common misconceptions students hold related to heat and temperature.
- Atoms get bigger when you heat them up
- Temperature and heat are the same thing
- Sweat cools you off in the same way as pouring cold water on you
- An object at 0 degrees has no heat
- When you touch a cold object, it transfers some of its coldness to you
- All ice is “0″ degrees Celsius
Facts
The following facts help correct these misconceptions:
- Heat does not rise. Heat cannot rise. Heat is not even a thing that could be seen even if it could rise. Heat is a form of energy.
- Atoms do not get bigger when they heat up, they only spread further apart when heated.
- Temperature and heat are not the same thing. An object can have high temperature and very little heat. An object can also have very low temperature and a lot of heat. Temperature is simply how fast molecules are moving in an object like books on a table. Heat is a form of energy that depends on the temperature as well as the type of molecule, and how many molecules in the object. Temperature is measured with a thermometer. Heat cannot be measured directly.
- Many students believe that sweat cools you down because water is cool. But sweat comes out at exactly the same temperature as your skin, maybe even a little hotter. It is not cool. So, how does it cool you then? It cools through evaporation.
- An object at 0 degrees Celsius or 0 degrees Fahrenheit does have heat. An object at 0 degrees Kelvin would not. There is one caveat, though . . . Although scientists have been very close to absolute zero, they have never reached it. It is not possible to have a temperature below 0 Kelvin so having negative heat is not possible. So it is accurate to say that everything on Earth and likely everything in the universe contains heat because everything has a temperature greater than 0 degrees Kelvin.
- Many students also believe that when they touch something cold, coldness is transferred from the cold object to their body. There is no such thing as cold. An object feels cold because it has less heat than you. The sensation of cold is the feeling that we get when heat leaves our body to enter an object with lower temperature. It is not coldness leaving the object and entering you, it is heat leaving you and entering the object.
- Many students believe that because the freezing point of water is 0 degrees C that all ice is at that temperature. But 0 degrees C is simply the maximum possible temperature for ice under normal conditions. If your freezer is set to -4 degrees C, then the ice cubes will be -4 degrees C. If it is -24 degrees C in Siberia, then the snow and ice there are at -24 degrees C.
Resource
Students Misconceptions in Science
Posted by David Wetzel
Interactive Online Math
PBS has developed online math games called Math Active, which allow students interact with the each game as they study specific math concepts. There are 31 games and are designed for middle school math. These games focus on Protractors - Angle Action.
All interactive math games involve solving problems and include teacher directions. Some games have both Spanish and Navajo language versions.
Online Math
The following are examples of what type of games are available on the Math Active website.
Cones, Cylinders, & Spheres
Classify prisms, pyramids, cones, and cylinders by base shape and lateral surface shape. Identify the net (two-dimensional representation) which corresponds to a rectangular prism, cone, or cylinder. Recognize the three dimensional figure represented by a net.
Pythagorean Theorem
Solve applied problems using the Pythagorean Theorem. Solve problems using special case right triangles.
Transformation Trio
Students observe many examples of rotation, translation, and reflection transformations. Students using problem solving techniques for selecting the called-for type of transformation.
Resources
Math Active
Math Teaching Strategies
Posted by David Wetzel
Borneo Rainforest
Wild and wondrous, rainforests extend from as far as Alaska and Canada to Latin America, Asia and Africa.
They nurture thousands of plants and animals found nowhere else on Earth and provide life’s essentials such as our medicines, food and water.
Temperate and tropical forests help regulate the Earth’s temperature and weather patterns.
Rainforests contain many of the essential plants used in the treatment of cancer.
Fifty percent of the world’s plants and animals can be found in these tropical forests.
Selected Threats
- More than half of Earth’s original rainforests have all been destroyed. They are the victims of unsustainable agriculture, ranching, logging, mining, and other destructive practices.
- Every year, 50 million acres, are cut down. India, Bangladesh, Sri Lanka and Haiti have been lost entirely, with the Ivory Coast fast approaching the same fate.
- Every second of every day, a slice of rainforest the size of a football field is mowed down. That’s 86,400 football field per day.
Other Quick Facts about
- Covering less than two percent of the Earth’s total surface area, these habitats are home to 50 percent of the Earth’s plants and animals.
- These forests can be found all over the world from as far north as Alaska and Canada to Latin America, Asia and Africa.
- Rainforests are found on every continent across the Earth, except Antarctica.
- There are two major types — temperate and tropical.
- The largest temperate rainforests are found on North America’s Pacific Coast and stretch from Northern California into Canada.
- Temperate forests used to exist on almost every continent in the world, but today only 50 percent – 75 million acres – of these forests remain worldwide.
- These habitats are critical in maintaining the Earth’s limited supply of drinking and fresh water.
- A typical four square mile patch contains as many as 1,500 flowering plants, 750 species of trees, 400 species of birds, and 150 species of butterflies.
Resources
Rainforest Facts
Fast Plants
