District of Columbia Public Schools Essential Knowledge and Skills for Science (Grade 8) DISTRICT OF COLUMBIA PUBLIC SCHOOLS, SCIENCE, Grade 8 SCIENCE Physical Science Content Standard 3: Understanding the concepts of matter, energy, motion and forces, which describe the physical world. Properties of Matter The student should know that: gas. In gases, the atoms or molecules have still more energy and are free of one another except during occasional collisions. SE/TE: How Can Air Keep Chalk From Breathing? 83; What Does a Graph of Gas, Pressure, and Temperature Show? 90; It s a Gas 94-95 SE/TE: 75, 83-89, 90-93 Guided Reading 185-187; Section Summary 184; Review and Reinforce 188; Enrich 189; Transparency PS23, PS24, PS25 TECH: Student Edition on Audio CD Gas Behavior; Lab Zone Easy Planner It s a Gas ; Lab Activity Video It s a Gas ; PresentationEXPRESS CD-ROM Gas Behavior; PHSchool.com cgp-1023 1
The temperature and acidity of a solution influence reaction rates. Many substances dissolve in water, which may greatly facilitate reactions between them. SE/TE: Temperature and Enzyme Activity 210-211 SE/TE: 207-209 Guided Reading 393-396; Section Summary 392; Review and Reinforce 397; Enrich 398; Transparency PS64, PS65, PS66 TECH: Student Edition on Audio CD Controlling Chemical Reactions; Lab Zone Easy Planner Temperature and Enzyme Activity ; Lab Activity Video Temperature and Enzyme Activity ; PresentationEXPRESS CD-ROM Controlling Chemical Reactions; PHSchool.com cgd-2023 Scientific ideas about elements were borrowed from some Greek philosophers of 2,000 years earlier, who believed that everything was made from four basic substances: air, earth, fire, and water. It was the combinations of these elements in different proportions that gave other substances their observable properties. The Greeks were about those four, but now over 100 different elements have been identified, some rare and some plentiful, out of which everything is made. Because most elements tend to combine with others, few elements are found in their pure form. SE/TE: 38-39 Guided Reading 107-109; Section Summary 106; Review and Reinforce 110; Enrich 111; Transparency PS10 TECH: Student Edition on Audio CD Describing Matter; PresentationEXPRESS CD-ROM Describing Matter; www.scilinks.org scn-1111 2
There are groups of elements that have similar properties, including highly reactive metals, less-reactive metals, highly reactive nonmetals and some almost completely nonreactive gases. (such as chlorine, fluorine, and oxygen; helium and neon) An especially important kind of reaction between substances involves combination of oxygen with something else as in burning or rusting. Some elements don t fit into any of the categories; among them are carbon and hydrogen, essential elements of living matter. SE/TE: Which is Easier 109; Why Use Aluminum 118; What are the Properties of Charcoal? 128; Show Me the Oxygen 132; Alien Periodic Table 136-137; What are the Trends in the Periodic Table? 150 SE/TE: 109-117, 118-127, 128-137, 138-141, 150-157 Guided Reading 240-242, 247-250, 257-260; Section Summary 239, 246, 256; Review and Reinforce 243, 251, 261; Enrich 244, 252, 262; Transparency PS35, PS36, PS38 TECH: Student Edition on Audio CD Organizing the Elements, Metals, Nonmetals and Metalloids, Radioactive Elements; Lab Zone Easy Planner Alien Periodic Table; Lab Activity Video Alien Periodic Table; PresentationEXPRESS CD-ROM Organizing the Elements, Metals, Nonmetals and Metalloids, Radioactive Elements; PHSchool.com cgp-1032; www.scilinks.org scn-1133, scn-1134 No matter how substances within a closed system interact with one another, or how they combine or break apart, the total weight of the system remains the same. The idea of atoms explains the conservation of matter: If the number of atoms stays the same no matter how they are rearranged, then their total mass stays the same. SE/TE: Still There 196 SE/TE: 53, 196-199 Guided Reading 384-388; Section Summary 383; Review and Reinforce 389; Enrich 390; Transparency PS60, PS61, PS62 TECH: Student Edition on Audio CD Describing Chemical Reactions; PresentationEXPRESS CD-ROM Describing Chemical Reactions; PHSchool.com cgp-2022, cgh-2020 3
Energy Transformation The student should know that: Energy cannot be created or destroyed, but only changed from one form into another. 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. SE/TE: What Would Make a Card Jump? 454; Pendulum Swing 458; Soaring Straws 460-461 SE/TE: What Would Make a Card Jump? 454; Pendulum Swing 458; Soaring Straws 460-461 SE/TE: 454-461 Guided Reading 318-320; Section Summary 317; Review and Reinforce 321; Enrich 322; Transparency PS146 TECH: Student Edition on Audio CD Energy Transformations and Conservation; Lab Zone Easy Planner Soaring Straws ; Lab Activity Video Soaring Straws ; PresentationEXPRESS CD-ROM Energy Transformations and Conservation; PHSchool.com cgp-3053 SE/TE: 447-461, 472-478 Guided Reading 309-310; Section Summary 308; Review and Reinforce 311; Enrich 312 TECH: Student Edition on Audio CD Forms of Energy, Thermal Energy, and Heat; Lab Zone Easy Planner Soaring Straws ; Lab Activity Video Soaring Straws ; PresentationEXPRESS CD-ROM Forms of Energy, Temperature, Thermal Energy, and Heat; www.scilnks.org scn-1352 4
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. SE/TE: What Would Make a Card Jump? 454; Pendulum Swing 458; Soaring Straws 460-461; Build Your Own Thermometer 478-479 SE/TE: 454-461, 479-485 Guided Reading 318-320; Section Summary 317; Review and Reinforce 321; Enrich 322; Transparency PS146 TECH: Student Edition on Audio CD Energy Transformations and Conservation, The Transfer of Heat; Lab Zone Easy Planner Soaring Straws, Build Your Own Thermometer 478-479; Lab Activity Video Soaring Straws, Build Your Own Thermometer 478-479; PresentationEXPRESS CD-ROM Energy Transformations and Conservation, The Transfer of Heat; PHSchool.com cgp- 3053 Heat can be transferred through materials by the collisions of atoms or across space by radiation. If the material is fluid, currents will be set up in it that aid the transfer of heat. SE/TE: Build Your Own Thermometer 478; What Does It Mean to Heat Up? 479; Feel the Warmth 482 SE/TE: 479-485 Guided Reading 376-378; Section Summary 375; Review and Reinforce 379; Enrich 380; Transparency PS151 TECH: Student Edition on Audio CD The Transfer of Heat; Lab Zone Easy Planner Build Your Own Thermometer 478-479; Lab Activity Video Build Your Own Thermometer 478-479; PresentationEXPRESS CD-ROM The Transfer of Heat; www.scilnks.org scn- 1362 5
Motion The student should know that: Light from the sun is made up of a mixture of many different colors of light, even though to the eye the light looks almost white. Other things that give off or reflect light have a different mix of colors. Something can be seen when light waves emitted or reflected by it enter the eye just as something can be heard when sound waves from it enter the ear. SE/TE: How Do Colors Mix? 610; Changing Colors 616 SE/TE: What is Sound? 540; How Does Amplitude Affect Loudness? 546; Pipe Sounds 550; How Can you Change Pitch? 552; Changing Pitch 557; How Do Colors Mix? 610; Changing Colors 616 SE/TE: 610-616 Guided Reading 247-249; Section Summary 246; Review and Reinforce 250; Enrich 251; Transparency PS196, PS197, PS198 TECH: Student Edition on Audio CD Light and Color; Lab Zone Easy Planner Changing Colors; Lab Activity Video Changing Colors; PresentationEXPRESS CD-ROM Light and Color; www.scilnks.org scn- 1543 SE/TE: 540-545, 546-551, 610-616 Guided Reading 113-115, 120-122, 247-249; Section Summary 112, 119, 246; Review and Reinforce 116, 123, 250; Enrich 251, 117, 124; Transparency PS196, PS197, PS198 TECH: Student Edition on Audio CD Light and Color, The Nature of Sound, The Properties of Sound; Lab Zone Easy Planner Changing Colors, Changing Pitch 557; Lab Activity Video Changing Colors, Changing Pitch 557; PresentationEXPRESS CD-ROM Light and Color, The Nature of Sound, The Properties of Sound; www.scilnks.org scn-1543, scn-1521; PHSchool.com cgd- 5022 6
An unbalanced force acting on an object changes its speed or path of motion, or both. If the force acts toward a single center, the object s path may curve into an orbit around the center. SE/TE: Is the Force With You? 334; Sticky Sneakers 338; Which Lands First? 340; What Changes Motion? 349 SE/TE: 334-339, 340-348, 349-352 Guided Reading 105-106, 115-118, 123-124; Section Summary 104, 114; Review and Reinforce 107, 119; Enrich 108, 120; Transparency PS109, PS111 TECH: Student Edition on Audio CD Forces; Lab Zone Easy Planner Sticky Sneakers 338; Lab Activity Video Sticky Sneakers 338; PresentationEXPRESS CD-ROM Forces; www.scilnks.org scn-1321, scn-1322 Vibrations in materials set up wavelike disturbances that spread away from the source. Sound and earthquake waves are examples. These and other waves move at different speeds in different materials. SE/TE: How Do Waves Travel? 510; Wavy Motions 520; Making Waves 528-529 SE/TE: 510-514, 515-520, 521-529, 530-535 Guided Reading 47-49, 54-56, 63-66, 74-76; Section Summary 46, 53, 62, 73; Review and Reinforce 50, 57, 67, 77; Enrich 51, 58, 68, 78; Transparency PS159, PS160, PS161, PS163, PS164, PS167, PS168, PS169, PS170 TECH: Student Edition on Audio CD Waves; Lab Zone Easy Planner Making Waves ; Lab Activity Video Making Waves ; PresentationEXPRESS CD-ROM Waves; PHSchool.com cgd-5012, cgp-5013; www.scilnks.org scn-1511, scn-1514 7
Human eyes respond to only a narrow range of wavelengths of electromagnetic radiation visible light. Differences of wavelength within that range are perceived as differences in color. SE/TE: How Do Colors Mix? 610; Changing Colors 616 SE/TE: 610-616 Guided Reading 247-249; Section Summary 246; Review and Reinforce 250; Enrich 251; Transparency PS196, PS197, PS198 TECH: Student Edition on Audio CD Light and Color; Lab Zone Easy Planner Changing Colors; Lab Activity Video Changing Colors; PresentationEXPRESS CD-ROM Light and Color; www.scilnks.org scn- 1543 Every object exerts gravitational force on every other object. The force depends on how much mass the objects have on how far apart they are. The force is hard to detect unless at least one of the objects has a lot of mass. The sun s gravitational pull holds the earth and other planets in their orbits, just as the planets gravitational pull keeps their moons in orbit around them. SE/TE: Which Lands First? 340; What Changes Motion? 349 SE/TE: What Makes an Object Move in a Circle? 362 SE/TE: 340-348 Guided Reading 115-118; Section Summary 114; Review and Reinforce 119; Enrich 120; Transparency PS111 TECH: Student Edition on Audio CD Friction and Gravity; PresentationEXPRESS CD- ROM Friction and Gravity; www.scilnks.org scn-1322 SE/TE: 344, 364 8
Electric currents and magnets can exert a force on each other. SE/TE: Are Magnetic Fields Limited to Magnets? 724; How Does a Magnet Move a Wire? 729; Building an Electric Motor 734-735; Can You Produce Current Without a Battery? 736 SE/TE: 724-728, 729-735, 736-741 Guided Reading 173-175, 180-182, 191-194; Section Summary 172, 179, 190; Review and Reinforce 176, 183, 195; Enrich 177, 184, 195; Transparency PS240, PS241, PS242 TECH: Student Edition on Audio CD Using Electricity and Magnetism; Lab Zone Easy Planner Building an Electric Motor ; Lab Activity Video Building an Electric Motor ; PresentationEXPRESS CD-ROM Using Electricity and Magnetism; PHSchool.com CGP-4033; www.scilnks.org scn-1431, SCN-1432 Reference: document provided in Hardcopy: DCPS SCIENCE STANDARDS FOR TEACHING AND LEARNING, Revised and Reformatted June 2004, DRAFT 9