Content Area: Earth Science Grade(s) 4. Essential Question(s) and Enduring Understandings

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1 Content Area: Earth Science Grade(s) 4 Unit Plan Title: Objects in the Universe Overview of Unit Students will make observations and record data to understand patterns of movement and relationships among the objects in the universe. They will explore the ways in which Earth is a part of the all-encompassing system of the universe. They will study how under the influence of gravitational forces, the solar system has developed its organizational patterns, and the patterns of movement of its component celestial bodies. Essential Question(s) and Enduring Understandings 1- Why do the Sun and Moon rise and set? Objects in the sky have patterns of movement that occur in specific sequences. We observe and record to learn about the universe. The Sun and Moon appear to move across the sky on a daily basis, and are explained by Earth s rotation. The shadows of an object on Earth change over the course of a day, indicating the daily rotation of Earth. The changing seasons relate to the orbital movements of Earth and the tilt of its axis of rotation. 2-Why does the shape of the Moon appear to change? The observable shape of the moon changes from day to day in a cycle that lasts 29.5 days. The shape changes because the Sun s light causes shadows that slowly vary as the moon revolves around Earth. 3- What is our solar system? Earth is the third planet from the Sun in our Solar System, which includes seven other planets that also revolve around the Sun and have different sizes, moons of their own, and different characteristics of their makeup. 4-Why is gravity an important force in our solar system? Observable, predictable patterns in the solar system occur because of gravitational interactions among the Sun and planets. The pull of the force of gravity within every planet also results in the approximately spherical shape of Earth and other planets and is the reason why objects fall towards the center of Earth.

2 Content Statements and CPIs All Science Practices standards for grade 4 need to be supported here: Objects in the sky have patterns of movement. The Sun and Moon appear to move across the sky on a daily basis. The shadows of an object on Earth change over the course of a day, indicating the changing position of the Sun during the day A.1 Formulate a general description of the daily motion of the Sun across the sky based on shadow observations. Explain how shadows could be used to tell the time of day. The observable shape of the Moon changes from day to day in a cycle that lasts 29.5 days A.2 Identify patterns of the Moon s appearance and make predictions about its future appearance based observational data. Earth is approximately spherical in shape. Objects fall towards the center of the Earth because of the pull of the force of gravity A.3. Generate a model with explanatory value that explains both why objects roll down ramps as well as why the Moon orbits Earth. Earth is the third planet from the Sun in our solar system, which includes seven other planets A.4 Analyze and evaluate evidence in the form of data tables and photographs to categorize and relate solar system objects (e.g., planets, dwarf planets, moons, asteroids, and comets).

3 Student Learning Targets/Objectives Students will be able to: Observe and record how the Sun, Earth s star, rises in the east and sets in the west in a predictable pattern; keep a Moon Journal and Sun Notebook of observations. Explain that Earth rotates on its axis, causing day and night. Day happens when a location on Earth is facing toward the Sun, and night happens when a location is facing away from the Sun. Explain that shadows are the areas of darkness created when an opaque object blocks light [review from grade 3] and that shadows on Earth depend on the position of the Sun in the sky. Include shadows in the Sun Notebook, which can be a whole-class activity. Learn that Earth is one of several planets that orbit the Sun in the solar system. Explain that the Moon orbits Earth and can appear in the sky during both day and night; observe and record in their Moon Journls how the Moon changes its appearance or phase in a regular pattern over 4 weeks. Use models to understand the movements of objects in the sky. Predict the outcome of an event and compare the results with the prediction. Strategies/Justifications Note-booking will help students clarify their own thinking, identify weaknesses and document progress. Identifying and listing objects in the Universe and their relationships will help students gain and organize information into a framework. Explaining the interactions of the objects in the Universe will help students understand the vocabulary and facts relating to the Solar System. Predicting how pieces of evidence fit into a larger schema will help students become aware of and alert to the big picture thinking. KWL will help students identify what they don t understand and how to revise their ideas. Grouping cooperatively will enhance learning and help solve complex problems

4 Teaching Points, Activities, and Assessments Teaching Point #1 Scientists review what is already known about a topic before starting investigations. Time Frame 2 x 40 minutes BEFORE STARTING THE UNIT: Help students start a journal to be part of their homework: Minimum 30 days (not necessary to do every night). Create a Moon Journal, remembering that the most important part about keeping a Moon Journal is to look for the Moon the same time each night. Make a very simple picture of where you see the Moon in the sky and be sure to include things like a house or tree in your picture. Try observations for several nights and learn to predict where the Moon will appear and what it will look like! Record a prediction and then record the actual observation. Label carefully. Instructions for a Moon Journal: Add a Sun Notebook as part of their record of celestial bodies: This can be done as a class chart keep in the classroom. Have them record each day for the length of the unit what time the sun rises and sets (check a newspaper or website). Do 6 observations (at 6 different times of the day) of the length of their shadows (work with a partner). Plan to debrief students on their obsevations during appropriate lessons. Lesson 1: Create a KWL chart to assess student understanding of objects in the universe, clarify any misconceptions, and identify questions that students can pursue during the unit. Build on prior knowledge and introduce vocabulary. Teacher Note: Use the probe The Two R s: Rotate and Revolve to help students learn the concepts behind the vocabulary, but use it after introducing and illustrating the words and their concepts. See page 30 of the probe to find a list of examples to help students differentiate betweem rotate and revolve: sun the star at the center of our solar system equator imaginary line going all the way around Earth halfway between the North and South Poles. axis an imaginary line that passes through the north and south poles rotate spin on its axis [If we can use spin instead of rotate, you will avoid a lot of confusion: if you must use rotate, then see the probe cited above and plan a quick activity from the probe to illustrate the difference.] revolve travel in a path around an object [Try to use orbit instead see the probe.] orbit to travel in a path around another object

5 Lesson 2: What is the shape of Earth? Teacher Note: It s time to make sure that students understand that Earth is round: use the probe, Is Earth Really Round? to stimulate discussion and find out who really does not envision Earth as a round planet, and don t be surprised if this is a big leap of faith for some students. We will return to these ideas in the last Teaching Point to learn why the planets are round. Take note of the evidence on page 8 of the probe that can be interjected into the class discussion to help students revise their thinking. Use the NASA website to show by zoom action how the ground we stand on is part of a spherical Earth. You can choose from a large number of locations and download the Quicktime video to you laptop. New York Central Park is a good local choice.

6 Teaching Point #2 The movement of the Earth results in day and night. 3 x 40 minutes Lesson 1: The night sky. Teacher Note: Use this probe to start a conversation about the movement of the Earth: Darkness at Night. This can be discussion or written. If you use written responses, then keep the students written responses to return for revisions later in the unit. Now investigate how night and day result from the spinning of Earth: explain that, like scientists, the class will use the MODEL below to explore how night and day happen. Sunrise, Sunset activity: use a high intensity flashlight and an inflatable globe to model day and night. Review the compass directions N,S, E, and W. Make sure the students turn the globe from west to east. Students should observe that sunrise occurs on the globe where it rotates from the shadow at the back of the globe to the light of the flashlight on the front of the globe. Sunset occurs where the globe rotates from light back into shadow. MAKE SURE EVERY STUDENT LAYS HANDS ON THE GLOBES AND CREATES THE SHADOWS NECESSARY TO UNDERSTAND. Lesson 2: Return to the Darkness at Night probe responses and have students check their thinking now. Make time to discuss, Where Do Stars Go, using the probe text to help generate discussion so students can begin to be clear about what they are observing in the night sky versus the day sky. Make use of ideas in another probe, Objects in the Sky, in preparation for the next lessons. Make sure they understand why we can often see the Moon in the daytime. Asking the probe question to generate discussion and elicit students ideas will move along how they make sense of the vocabulary, models, and concepts. Lesson 3: The length and direction of shadows can be used to tell time. Take students outdoors on a sunny day to measure their shadows and decide on the directions that the shadows point. Plan to do this on a few days, early morning, late morning, and late in school day.

7 Teaching Point #3 There is a time/space relationship between Earth, Moon and the Sun. 40 minutes This activity can be done as a fishbowl with a small group of students demonstrating to the rest of the class, who are commentators. Moving through space activity: using a beach ball, baseball and ping-pong ball, model the movements of Sun, Earth, and Moon. SEE ATTACHED IMAGE of textbook page at end for procedure. Teacher Note: Students need time to make sense of all this. Return to the probe responses for Objects in the Sky and discuss whether or not students learned something new. Administer probe, Emmy s Moon and Stars to see if they understand that there are no stars between the Earth and the Moon, and that stars are all very far away even farther than our star, the Sun. This can be modeled with the balls again by adding paper stars at distant locations. Teaching Point #4 Seasonal changes are the result of the tilt of Earth s axis. 40 minutes Using an inflatable globe mark the North Pole and another point indicating North America. Then have them tilt the North Pole toward the flashlight and rotate the globe so that the North Pole stays in the light. It is our Summer when North America is on the sun side. On the opposite side of the Northern Hemisphere it is Winter. Assessment A friend lives where there are 12 hours of daylight every day. Where does this person live, and how do you know? What season is it in the Northern Hemisphere when the Southern Hemisphere points towards the sun? Teacher use only for background: SEE the Probe, Why is it Warmer in Summer? and note that experts say that 4 th graders are not expected to understand the reason why seasons occur. This concept is difficult for college students. But hope for the best.

8 Teaching Point #5 Earth is the third planet from the Sun in our solar system, which includes seven other planets. 3 to 4 40 minute periods Lesson 1: Research, analyze and evaluate evidence in the form of data tables provided from the Smartboard activity Let s Explore Our Solar System Notebook activity. Research the criteria used to categorize objects as planets and show photographs to help students visualize the planets and other objects in our solar system. Use this link to show a graphic comparison of the size of Earth compared with other planets and other objects in the Universe: Data include size, distance from the sun, gravitational force/weight, length of year, number of moons. Help students relate the data to the objects in the solar system (e.g., planets, moons). Lesson 2: Examine more information on the names, mythology, and characteristics of Earth & planets in our solar system using this link: Lesson 3: Add more detail and comparisons of planet data using the Planet worksheet link and help students complete pages in their notebooks describing and comparing the planets. Students can add this coloring book image to their notebooks (also at the end of this unit plan: if you drag the corners of the image, you can enlarge it for printing.)

9 Teaching Point #6 The observable shape of the moon changes from day to day in a cycle that lasts 29.5 days. 2 x 40 minutes Lesson 1: Have students share and review their Moon Journals and discuss what they think is going on with the Moon. Suggest that scientists often use MODELS to figure out difficult problems. Suggest that they could make a model to help explain why the moon has phases. Experiment with why the Moon has phases. Use a bright flashlight and a ball on a stick. Whoever is holding the flashlight becomes the Sun and the Earth is your head. If you hold the ball out at arm s length just above the flashlight while facing the Sun, you can t see it. This is New Moon. The Moon is still in the sky, but we can t see it because of the bright sunlight. Now keep the ball at arm s length and turn slowly counterclockwise and watch what happens. That s right! You see the ball go through phases, just like our Moon. When your back is towards the Sun, you see the ball as whole, and it will be Full Moon. The Moon will rise on the opposite side of the Earth at the same time the Sun goes down. Keep turning and you ll see the phases reverse as the Moon moves back towards the Sun again. Use published lunar phase data to make predictions. Available daily in newspapers and online. Lesson 2: Another model- Oreo Moon Phases activity links: ases.pdf Phases of the Moon realistic picture link: Administer the probe Going Through A Phase, but bear in mind that elementary students are not expected to understand the reason why the moon has phases. They are only expected to recognize the pattern. See Teacher Notes accompanying this probe.

10 Teaching Point #7 Objects are attracted toward the center of the earth because of the pull of the force of gravity. 40 minutes Start lesson with the Experiencing Gravity probe, to begin discussion of the students ideas about gravity. Gravity and inertia using glass, card and coin: First set up the card, coin and glass and ask students to predict what will happen if you flick the card off the glass: will the coin move with the card, will the coin fall into the glass, will the coin get shot off to the side, or what? Have them write their predictions in their notebooks with diagrams. Then do the demo: you had better practice!! Next discuss the Apple on the Ground probe to develop their ideas about gravity. Falling Objects activity: Ask for their predictions about what will happen in this gravity experiment using two different balls, wadded paper and a rock. Have them write their predictions in their notebooks or on worksheets. Use the following link with activity and assessment sheet, or use their notebooks (procedure is also included at the end of this plan). df Moon Walk version of dropping objects to show equal pull of gravity: At the end of the last Apollo 15 moon walk, Commander David Scott performed a live demonstration for the television cameras. He held out a geologic hammer and a feather and dropped them at the same time. The Apollo 15 Hammer-Feather Drop is found at:

11 Teaching Point #8 Earth and other planets are spherical because the force of gravity acts in every direction within a body of matter. One of the effects of mass is that it attracts other mass. For small objects, like your computer, your car, and even a building, the force of gravity is tiny. But when you have millions, and even trillions of tons of mass, the effect of the gravity really builds up. All of the mass pulls on all the other mass, and it tries to create the most efficient shape a sphere. 1 x 40 minute period To understand why Earth and other planets all have a round spherical shape, think about rain drops. Seeing falling raindrops is difficult, however small raindrops have a spherical shape. The popular conception that raindrops are teardrop shaped is incorrect. Small raindrops are spherical. Larger raindrops are distorted by air pressure as they fall. In space floating water drops would all be spherical. Blobs of liquid with no other significant forces acting on them will take on a spherical shape. Liquids will be round spheres whether they are the size of raindrops, planets, or stars. Earth and other solid planets are spherical because they were once liquids. Scientists call both liquids and gasses fluids. Stars and the large gas giant planets are mostly spherical because gas flows easily like liquid and the same forces are at work. Activity with water drops: to show how they form spheres because of the attractions among the water molecules, and because a sphere is the most economical shape for a lump of matter: [Teacher note: see if it is necessary to dye the water with a food coloring to enhance the visibility of the water drops.] Students should fill an eyedropper with water and place the tip far into a clear cup of oil. Do not squeeze until everyone can clearly see the tip of the dropper from a side view. Squeeze out the water and watch what happens. Take careful note of the shape and behavior of the drop and record your observations. Why do you think the drops took the shape they did? Key Ideas: a) Water particles are attracted to other water particles. [Check that the students understand that liquids are made up of particles that move a lot. The same for gases, only they move more rapidly and freely.] b) Water forms spheres. c) The reason water drops form spheres is that the water particles want to get as close together as possible. Planets and stars are much larger than water drops and have a total mass that can produce a very large force of gravity. So a planet is round both because it started as a liquid and gas and then gravity helped round out the shape.. Gravity pulls equally in all directions. Suppose you had a great big, tall mountain. As time goes by, rocks and dirt loosen up and fall down the mountain side. Eventually the mountain is worn down. Similarly a deep, deep valley will fill up. Of course a planet is not perfectly round look at the mountains and valleys on the Earth and on Mars! Also the bigger the planet, the stronger the gravity. So bigger planets will be rounder. Tiny planets may not be very round. For instance, some of the moons around Jupiter are not very big and are not round sort of oblong and irregular. Asteroids, which may be only a few miles long, are also irregular.

12 Benchmark Assessment Unit Resources Oreo Cookies 4 per child Popsicle sticks 25/class School Specialty -School Smart Craft Sticks 41/2 x 3/8 - Pack of 1,000 Natural Item # Catalog Price $7.25 Clear cups (12), eyedroppers, and cooking oil (32 oz) maybe some food coloring On the shared drive: Probes from Page Keeley volumes The Two R s: Rotate and Revolve Is Earth Really Round? Darkness at Night Where Do Stars Go? Objects in the Sky Emmy s Moon and Stars Why is it Warmer in Summer? teacher background only! Going Through A Phase Experiencing Gravity Apple on the Ground Technological Resources Technology to be integrated (tools, equipment, software, and online learning) As linked within plan.