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Science Grade 08 Unit 11 Exemplar Lesson 02: Classifying Stars Page 1

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Science Grade 08 Unit 11 Exemplar Lesson 02: Classifying Stars Page 1 Grade 8 Science Unit: 11 Lesson: 02 Suggested Duration: 7 days Science Grade 08 Unit 11 Exemplar Lesson 02: Classifying Stars This lesson is one approach to teaching the State Standards associated with this unit. Districts are encouraged to customize this lesson by supplementing with district-approved resources, materials, and activities to best meet the needs of learners. The duration for this lesson is only a recommendation, and districts may modify the time frame to meet students’ needs. To better understand how your district may be implementing CSCOPE lessons, please contact your child’s teacher. (For your convenience, please find linked the TEA Commissioner’s List of State Board of Education Approved Instructional Resources and Midcycle State Adopted Instructional Materials.) Lesson Synopsis In this lesson, students describe components of the universe and use the Herztsprung-Russell diagram to classify stars. They will identify the Sun as a medium-sized star near the edge of a disc-shaped galaxy of stars and understand that it is thousands of times closer to Earth than other stars. TEKS The Texas Essential Knowledge and Skills (TEKS) listed below are the standards adopted by the State Board of Education, which are required by Texas law. Any standard that has a strike-through (e.g. sample phrase) indicates that portion of the standard is taught in a previous or subsequent unit. The TEKS are available on the Texas Education Agency website at http://www.tea.state.tx.us/index2.aspx?id=6148. 8.8 Earth and space. The student knows characteristics of the universe. The student is expected to: 8.8A Describe components of the universe, including stars, nebulae, and galaxies, and use models such as the Herztsprung-Russell diagram for classification. Readiness Standard 8.8B Recognize that the Sun is a medium-sized star near the edge of a disc-shaped galaxy of stars and that the Sun is many thousands of times closer to Earth than any other star. Supporting Standard Scientific Process TEKS 8.2 Scientific investigation and reasoning. The student uses scientific inquiry methods during laboratory and field investigations. The student is expected to: 8.2E Analyze data to formulate reasonable explanations, communicate valid conclusions supported by the data, and predict trends. 8.3 Scientific investigation and reasoning. The student uses critical thinking, scientific reasoning, and problem solving to make informed decisions and knows the contributions of relevant scientists. The student is expected to: 8.3A In all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, including examining all sides of scientific evidence of those scientific explanations, so as to encourage critical thinking by the student. 8.3B Use models to represent aspects of the natural world such as an atom, a molecule, space, or a geologic feature. 8.3C Identify advantages and limitations of models such as size, scale, properties, and materials. 8.3D Relate the impact of research on scientific thought and society, including the history of science and contributions of scientists as related to the content. 8.4 Scientific investigation and reasoning. The student knows how to use a variety of tools and safety equipment to conduct science inquiry. The student is expected to: 8.4A Use appropriate tools to collect, record, and analyze information, including lab journals/notebooks, beakers, meter sticks, graduated cylinders, anemometers, psychrometers, hot plates, test tubes, spring scales, balances, microscopes, thermometers, calculators, computers, spectroscopes, timing devices, and other equipment as needed to teach the curriculum. GETTING READY FOR INSTRUCTION Performance Indicators Grade 08 Science Unit 11 PI 02 Create a field guide for stars, including our Sun, a supergiant, a giant, a main sequence star, and a dwarf star. Provide a description, relative age and life span, luminosity, and temperature of each star. Finally, describe how models such as a Hertsprung-Russel diagram can be used for classification. Standard(s): 8.2E , 8.8A , 8.8B ELPS ELPS.c.1C , ELPS.c.2C , ELPS.c.5B Key Understandings Last Updated 06/03/13 page 1 of 32 Grade 8 Science Unit: 11 Lesson: 02 Suggested Duration: 7 days All stars are not the same in size, age, and temperature. — How are galaxies classified? — Where is our Sun located in the Milky Way galaxy? — What characteristics are used to classify stars? — How are stars classified on an H­R diagram? — Once a star has been identified as a main sequence star, will it always remain in that area on an H­R diagram? — What factor determines the life cycle a star will have? — How is the life cycle of a main sequence star different from the life cycle of a massive star? — How is our Sun classified as a star? — What star is closest to Earth? Vocabulary of Instruction star neutron star spiral galaxy protostar black dwarf star irregular galaxy main sequence star black hole barred-spiral galaxy universe galaxy luminosity red giant star stellar nebula Hertzsprung-Russell diagram red supergiant star planetary nebula absolute magnitude white dwarf star elliptical galaxy apparent magnitude Materials tape or glue (per class) flashlights (identical basic, 2 per teacher demonstration) flashlight (bright LED bulb(s), 1 per teacher demonstration) Group HR Diagrams (see Advance Preparation, 1 per group) paper (butcher, white, 1 sheet per group) marker (per teacher) tape (masking, per group) colored pencils (blue, yellow, orange, and red, 1 per student) pencil (1 per student) paper (plain, multiple sheets per class) paper (various per class) colored pencils (per class) Attachments All attachments associated with this lesson are referenced in the body of the lesson. Due to considerations for grading or student assessment, attachments that are connected with Performance Indicators or serve as answer keys are available in the district site and are not accessible on the public website. Teacher Resource: Galaxies and Stars Cards (see Advance Preparation, 1 set per group) Handout: Galaxies (1 per student) Teacher Resource: Galaxies KEY Handout: Galaxies and Stars Questions (1 per student) Teacher Resource: Galaxies and Stars Questions KEY Teacher Resource: PowerPoint: Galaxies and Stars Teacher Resource: Human Life Cycle Cards (see Advance Preparation, 1 set per pair) Teacher Resource: Star Life Cycle Cards (see Advance Preparation, 1 per group) Handout: Life Cycle of Stars Graphic Organizer (1 per student) Teacher Resource: Life Cycle of Stars Graphic Organizer KEY Teacher Resource: PowerPoint: Star Life Cycle Handout: Galaxies and Stars (1 per student) Teacher Resource: Galaxies and Stars KEY Teacher Resource: Power Point: Star Classification Teacher Resource: H-R Diagram Samples Teacher Resource: Power Point: H-R Diagram Handout: Stars from Afar (1 per student) Teacher Resource: Stars from Afar KEY Last Updated 06/03/13 page 2 of 32 Grade 8 Science Unit: 11 Lesson: 02 Suggested Duration: 7 days Teacher Resource: Stars from Afar Graph KEY Teacher Resource: Performance Indicator Instructions KEY (1 for projection) Resources None Identified Advance Preparation 1. Prior to Day 1: Print on cardstock, laminate, cut apart, and bag the cards of the Teacher Resource: Galaxies and Stars Cards. You will need one set per group. Arrange for student computer/Internet use for Days 1, 2 and 7. 2. Prior to Day 2: Print on cardstock, laminate, cut apart, and bag the cards of the Teacher Resource: Human Life Cycle Cards. There are four sets per page, and you will need one set per pair of students. Print on cardstock, laminate, cut apart, and bag the cards of the Teacher Resource: Star Life Cycle Cards. There are three sets per page, and you will need one set per group. 3. Prior to Day 5: Assemble Star Sets for star classification activity. Print on cardstock, laminate, cut apart, and bag Teacher Resource: Power Point: Star Classification. You will need one set per group. The following site may be used to develop the background and connection between the visible spectrum and the color and temperature of stars. Create group H-R diagrams for star classification activity. Use one large piece of white butcher paper for each diagram. See the Handout: Stars from Afar page 3 for an example. Laminate to increase durability. You will need one diagram per group. 4. Prior to Day 6: Perform a web search for an approved interactive H­R diagram. You may find it helpful to include the terms “aspire and HR interactive” in your search. 5. Prepare attachment(s) as necessary. Background Information This unit bundles student expectations that address components and characteristics of the universe. Students learn that stars and galaxies are part of the universe and how they can be classified by their characteristics. Prior to this unit, in Grade 8, students studied the effects resulting from cyclical movements of the Sun, Earth, and Moon. Cycles within the Earth, Sun, and Moon systems are studied as students learn about seasons, tides, and lunar phases. During this lesson, students will study the components of the universe. This will be the first time students investigate the universe beyond our solar system, including the properties of components in the universe. They also recognize that the Sun is a medium-sized star near the edge of a disc-shaped galaxy of stars and will describe components of the universe, including stars, nebulae, and galaxies and use models such as the Herztsprung-Russell diagram for classification. STAAR Note: Readiness Standard (8.8A), the components of the universe and models such as the Herztsprung-Russell diagram, Supporting Standard (8.8B), recognition of the sun as a medium-sized star near the edge of a disc-shaped galaxy, and Supporting Standard (8.8C), exploring how different wavelengths of the electromagnetic spectrum, are used to gain information about distances and properties of components in the universe will be assessed under Reporting Category 3: Earth and Space on the STAAR Grade 8 Science Assessment.
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