Alaska Science Key Element A8b A student who meets the content standard should understand the scientific principles and models that state whenever energy is reduced in one place, it is increased somewhere else by the same amount (Energy Transformations).
 Performance Standard Level 3, Ages 11–14 Students observe and describe energy changes that take place around them. Sample Assessment Ideas Students draw a diagram to show the flow of energy from the fuel used in the local generator to the electric light in their respective homes. Students research the energy efficiency of their home and develop multiple suggestions as to how to improve the heat efficiency of their respective homes. Expanded Sample Assessment Idea Students create a model of a steam house; measure the temperature changes; explain the energy transfers. [Proper SAFETY precautions should be used.]
 Procedure Students will: Build a model of a steam house or steam tent. Measure the weight of a length of metal chain. Heat the metal chain on a hot plate. (Note: chain makes a good substitute for rocks which sometimes explode when heated.) Remove the chain and place it inside the model. Carefully pour a measured amount of water over the chain. Measure the increase in temperature inside the model. Explain how the temperature measurement and calculations describe each of the energy releases and transfers. (Be sure to include the energy needed to turn liquid water into water vapor.) Reflection and Revision Discuss energy transfer by radiation, conduction and convection. Give examples in nature of where these energy transfers occur. Give examples of where these energy transfers occur in our technological world. Levels of Performance Stage 4 Student work is complete, correct and shows detailed evidence of the transfer and extension of knowledge related to energy changes that take place around us. The experiment is performed safely, data is represented with appropriate units, explanation is accurate and describes examples of radiation, conduction and convection in the natural environment as well as in the technological world. Stage 3 Student work is mostly complete, correct and shows evidence of the transfer or extension of knowledge related to energy changes that take place around us, but may contain minor errors or omissions.. The experiment is performed safely, data may not include appropriate units, and the explanation describes at least two examples of radiation, conduction or convection in the natural environment or in the technological world, although it may contain minor errors or omissions. Stage 2 Student work may be incomplete, and shows limited evidence of knowledge related to energy changes that take place around us. The experiment is performed safely and model may show evidence of skilled craftsmanship but data is incomplete or incorrect, and the explanation may contain misconceptions. Stage 1 Student work is mostly incomplete, inappropriate, shows little evidence of craftsmanship or knowledge related to energy changes that take place around us.
 Standards Cross-References ( Alaska Department of Education & Early Development Standards) National Science Education Standards Energy is a property of many substances and is associated with heat, light, electricity, mechanical motion, sound, nuclei, and the nature of a chemical. Energy is transferred in many ways. (Page 155) Electrical circuits provide a means of transferring electrical energy when heat, light, sound, and chemical changes are produced. (Page 155) In most chemical and nuclear reactions, energy is transferred into or out of a system. Heat, light, mechanical motion, or electricity might all be involved in such transfers. (Page 155) The sun is a major source of energy for changes on the Earth’s surface. The sun loses energy by emitting light. A tiny fraction of that light reaches the Earth, transferring energy from the sun to the Earth. The sun’s energy arrives as light with a range of wavelengths, consisting of visible light, infrared, and ultraviolet radiation. (Page 155) Benchmarks Energy cannot be created or destroyed, but only changed from one form into another. (Page 85) Most of what goes on in the universe—from exploding stars and biological growth to the operation of machines and the motion of people—involves some form of energy being transformed into another. Energy in the form of heat is almost always one of the products of an energy transformation. (Page 85) Energy appears in different forms. Heat energy is in the disorderly motion of molecules; chemical energy is in the arrangement of atoms; mechanical energy is in moving bodies or in elastically distorted shapes; gravitational energy is in the separation of mutually attracting masses. (Page 85)