Grade 3 Gravity is a Force Topic XI Big Idea 5: Earth in Space and Time Division of Academics - Department of Science

Benchmarks SC.3.E.5.4:SC.3.E.5.4: Explore the Law of Gravity by demonstrating that gravity is a force that can be overcome. SC.3.N.1.3: Keep records as appropriate, such as pictorial, written, or simple charts and graphs, of investigations conducted. LAFS.3.SL.1.1: Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 3 topics and texts, building on others’ ideas and expressing their own clearly. Division of Academics - Department of Science

What happens when you trip? You fall down. What happens when you throw a ball up in the air? No matter how high it goes, it always falls back on Earth. Do you know what makes things fall? That’s right. GravityGravity Division of Academics - Department of Science

GravityGravity is a force that is always pulling objects down. What makes things fall down? Division of Academics - Department of Science

Gravity (Sung to “London Bridge is Falling down”) Gravity is pulling down, Pulling down, Pulling down. Gravity is pulling down All around you! Take a ball and toss it high. Will it stay in the sky? Gravity will pull it down All around you. Gravity is pulling down, Pulling down, Pulling down. Gravity is pulling down All around you! Jump up high and down you’ll go. There’s a force down below. Gravity is pulley down All around you Division of Academics - Department of Science

Gravity Division of Academics – Department of Science Scroll over the black screen and click. Did you learn anything new from the video about gravity? Explain.

GravityGravity is the force that pulls things toward the center of the Earth. Division of Academics - Department of Science

Try Discovery Education Exploration: GravityGravity Copy the two column chart in your science notebook. Now open the Gravity Exploration.Gravity Read the Introduction. Then click on the objects one at a time to see how gravity affects them. Write your responses on the chart you copied from below.

Discovery Education Exploration: Gravity ContinuedGravity 1. On which planet is it easiest to lift a bowling ball? 2. On which planet could you get a soccer ball the farthest? Copy the chart below and then click on Next in the Gravity Exploration.Gravity Follow directions to click on pictures of objects to see how much they weigh on different planets.

What do YOU know about gravity? Pulls things down toward the center of the Earth Can act on things far away Keeps objects in orbit Gets weaker as you move farther from Earth Division of Academics - Department of Science

Meet “Fearless” Felix Division of Academics - Department of Science

What do you NOW know about gravity? Division of Academics – Department of Science 1.What is gravity? 2.What does gravity do? 3.Why is it harder to lift a bowling bowl than a tennis ball? Answer: A bowling ball has more mass than a tennis ball, so the pull of gravity on the bowling ball is greater than the pull of gravity on the tennis ball. 4. List some examples of how gravity affects us everyday.

Sir Issac Newton 300 years ago, this scientist was in his garden, when an apple fell from a tree. Newton had a sudden brainstorm. He connected the force that caused the apple to fall to the force that kept the moon “tied” in orbit around the Earth. In more scientific words, he began to discover the theory of gravity. Division of Academics - Department of Science

Why did the book fall to the table? When I held up the book, what force was I overcoming? Why did it stop on the desk and not go to the ground? Press the side of a hand against the edge of a table. What do you notice? You can feel the desk exerting a force on your hand. Now press harder. The harder you press the harder the desk pushes back on your hand. Division of Academics - Department of Science

What is all around us? That’s right… airair What do you know about air? It is made up of oxygen, nitrogen and other gases. All living things breathe air. It moves a lot. Let’s watch the Five Air Facts video.Five Air Facts What else did you learn about air? It has weight. It can contain water vapor. Division of Academics - Department of Science

Let’s investigate air How are these two pieces of paper alike? Same size and shape I’m crumpling one up. Now observe what happens to these two pieces of paper as I drop them. What happened? The crumpled ball went straight down, while the flat sheet floated down, moving all about. Why? The air is pushing against the flat sheet of paper with more surface area, causing friction to slow it down. More contact, more friction. Division of Academics - Department of Science

How did air affect gravity's pull on the paper? The air pushing up against the flat paper caused friction between the two affecting gravity’s pull. This force is called air resistance. To prove this defying of gravity, astronauts d ropped a hammer and a feather on the moon where there is no air. Let’s watch the video: What would happen on Earth, would the objects hit the ground at the same time? No, the feather would have more friction with the air, it has more surface area). Division of Academics - Department of Science

What are some examples of ways that we "defy" gravity? rockets airplanes jumping up sitting in a chair Division of Academics - Department of Science

Stop the Drop - An Engineering Design Challenge Imagine you live in an apartment complex, on the 2nd floor that has a balcony overlooking the pool area. You are up watching a movie but your mom is at the pool and has just texted, asking you to bring down a cup of water. You don't want to walk to the pool, it is a long way and you will miss your movie! You would like to just drop the water to your mom, she is right there, so close! You take a paper cup, fill it with water and drop it to your mom. It lands on the ground. As you are getting another cup of water, resigned to the long walk and missing the movie, you think, "There has to be a way to set the cup down softly!" Division of Academics - Department of Science

Are you ready for a challenge? Can we defy gravity to bring a cup of water to the ground safely? You will be engineers in this design challenge. What do you know about engineers and the work they do? Division of Academics - Department of Science

The goal is to not lose any water, not even a drop In your engineering group: brainstorm ideas and design considerations, coming up with multiple possibilities, determine which design they will focus on, each member will be required to draw and label the design on an Engineer's Report form. You must bring your plans to the Project Head (teacher) for approval before building the prototype. Division of Academics - Department of Science

Project Specifications Each Engineering group will be given the same materials to work with. See Materials list. You will only get new index cards between each test; no additional materials will be given out. You may use all the string and tape they want, no limit on those but you MUST be careful before they cut something, you won't get a new one. Nothing may cover the cup. All materials must be a minimum of 15 cm above the cup opening The cup of water will be dropped by the Project Head from the top of a chair/table. All cups will have the same starting elevation. Each group will have 50 ml of water in a graduated cylinder. You will pour the water into the cup just before the test and then later measure the amount of water that remains in the cup after landing. Division of Academics - Department of Science

Project Materials - 4 index cards per testing round (they get wet and need to be replaced) – 4 straws – 4 Popsicle sticks – 4 rubber bands – 2 pipe cleaners/chenille stems – half of a plastic Publix/Wal-Mart/Target bag (don't give them the whole bag) – 1 roll of masking tape (no limit on the amount) – String (no limit on the amount) – Anything else you can think of to include – Small Dixie cup (will need 50 ml of water) – Graduated cylinder Division of Academics - Department of Science

Sample Data Chart Starting VolumeEnding VolumeWater Lost Test 1 Test 2 Division of Academics - Department of Science

The Final Engineer's Report Each student works on the analysis on his/her own. 1.How successful was your team’s project? Use evidence from the "Drop-off” for support. 2.What are the successful design components (parts that worked well) that you did to overcome gravity? 3.What are the areas that didn’t work well. Why? 4. Which did you find the most challenging? Why? Division of Academics - Department of Science

Alternate AIMS Investigation: Gravity-Defying Olympics Essential Question: What are some ways that gravity can be overcome? Learning Objectives: Participate in a series of gravity-defying events. Recognize that gravity is a force that can be overcome. Division of Academics - Department of Science

Gravity-Defying Olympics Connected Learning 1.How do you know that gravity exists? 2.What are some things that you can do to overcome gravity? 3.Which Olympic event did you find the easiest?...most challenging? Why? 4.Why do you think we found the median average score for the events? 5.What are you wondering now? Division of Academics - Department of Science