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DESCRIPTION

Simple explanations and experiments using soap and sponges help clarify why some objects float and some sink. Explains why boats usually don't sink, and shows many different boats.

ACADEMIC STANDARDS

Subject Area: Science

• Standard: Understands basic concepts about the structure and properties of matter

§ Benchmark: Knows that properties such as length, weight, temperature, and volume can be measured using appropriate tools (e.g., rulers, balances, thermometers, graduated cylinders) (See Instructional Goal #2)

§ Benchmark: Knows that different objects are made up of many different types of materials (e.g., cloth, paper, wood, metal) and have many different observable properties (e.g., color, size, shape, weight) (See Instructional Goals #1 and #3)

• Standard: Understands the nature of scientific inquiry

§ Benchmark: Knows that tools (e.g., thermometers, magnifiers, rulers, balances) can be used to gather information and extend the senses (See Instructional Goal #2)

§ Benchmark: Knows that learning can come from careful observations and simple experiments (See Instructional Goals #4 and #6)

Subject Area: Geography

• Standard: Understands the patterns and networks of economic interdependence on Earth’s surface

§ Benchmark: Knows the modes of transportation used to move people, products and ideas from place to place (e.g., barges, airplanes, automobiles, pipelines, ships, railroads), their importance and their advantages and disadvantages (See Instructional Goal #5)

INSTRUCTIONAL GOALS

1. To compare things that sink and things that float. 2. To provide a simple explanation of mass by using a balance scale. 3. To illustrate that things filled with air float. 4. To demonstrate science experiments related to sinking and floating. 5. To show a variety of boats. 6. To provide directions and a demonstration for making a toy boat.

VOCABULARY

1. balance (scale) 2. mass 3. sink 4. float 5. ocean liner 6. passengers

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7. cargo 8. canoe 9. trawler

10. freighter 11. kayak 12. ferry 13. submarine

BEFORE SHOWING

1. Provide balance scales. Experiment with the balance scales using a variety of objects. Discuss the results using the comparative and superlative forms of heavy and light.

2. Experiment with sinking and floating a variety of objects. Hypothesize why things float or sink. Record results on a chart. (See INSTRUCTIONAL GRAPHICS.)

DURING SHOWING

Discussion Items and Questions

1. View the video more than once, with one showing uninterrupted. 2. On the first viewing, pause the video to predict what will happen in each experiment. 3. Review the boat section of the video. Pause to identify each type of boat by name. Discuss the purpose

of each kind of boat. Look for small boats with the large boats.

AFTER SHOWING

Discussion Items and Questions

1. Why does the dry sponge float and the wet sponge sink? 2. Explain why the plasticine and the little container that have the same mass behave differently in the

water. 3. Why does a balloon with air inside float and a balloon with water inside sink? 4. Explain why one bar of soap might float and another bar of soap might sink. 5. Why do very large, heavy ships float? 6. Describe two reasons a boat might sink. 7. Recall the names of the different kinds of boats shown in the video. Identify the purpose of each kind. 8. How does a submarine go up and down in the water? 9. Why does the milk carton boat float? How does it move across the water?

Applications and Activities

1. Experiment with sinking and floating a variety of objects. Record results on a chart. (See INSTRUCTIONAL GRAPHICS.)

2. Research how submarines move in the water. Perform the submarine experiment shown in the video. Relate the experiment to how submarines actually rise and submerge in the water.

3. Investigate the use of a balance for measuring mass. Compare the mass of various objects. Use actual gram and kilogram weights to accurately measure the mass of objects.

4. Make a boat with plasticine or modeling clay. Test it to see if it floats. Then take the same piece of clay and wad it up into a ball. Test it again to see if it floats. Discuss the results.

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5. Research the history of boats and ships. Create a timeline showing the development of boats throughout history.

6. Make a mural showing a variety of boats. 7. Make a sailboat from a milk carton as shown in the video. Make sailboats with other materials. Test the

boats to see which kind floats the best. Race the boats to see which goes the farthest or fastest. 8. Research and report on a variety of boats. Include history, size, and uses. 9. Locate the name of the boat used in the Everglades that goes above the water. Investigate how it works.

10. Investigate the Titanic. a. Was it overloaded? b. What caused it to fill with water? c. How did it actually sink?

Experiments

1. Test foil boats. a. Shape pieces of foil into boats. b. Float the boats in water. c. Add pennies one at a time until the boats sink. d. Record how many coins each boat can hold before it sinks. e. Compare the results.

2. Make a Cartesian diver. a. Fill a large drinking glass with room-temperature water. b. Gradually draw water into an eyedropper until the eyedropper floats in the glass with its top barely

above the surface. c. Fill an empty two-liter plastic soda bottle almost to the top with room-temperature water. d. Transfer the eyedropper into the soda bottle. Be careful not to change the amount of water in the

dropper during the transfer. e. Screw the cap tightly onto the soda bottle. f. Squeeze the soda bottle to make the eyedropper (diver) sink, rise, or hover at any depth.

3. Sink a can. a. Place a small empty frozen juice can in a pail of water. b. Fill a glass measuring cup to the top mark. c. Pour water from the measuring cup into the juice can just until the can floats upright in the pail of

water. d. Record how much water was added from the measuring cup. e. Use a ruler to measure how far the can has sunk into the water. Record that result. f. Add water equal to the amount already in the juice can. g. Measure the depth of the can in the pail of water and record the results. h. Continue adding equal amounts of water and measuring the depth until the can sinks. i. Analyze the results. Explain the relationship between the amount of water added each time and the

extent to which the can sinks.

INSTRUCTIONAL GRAPHICS

• SINK OR FLOAT?

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RELATED RESOURCES

Captioned Media Program

• Boats and Ships #1467 • Learning About Water #1389 • Transportation: A Basic Need #1441

World Wide Web

The following Web sites complement the contents of this guide; they were selected by professionals who have experience in teaching deaf and hard of hearing students. Every effort was made to select accurate, educationally relevant, and “kid-safe” sites. However, teachers should preview them before use. The U.S. Department of Education, the National Association of the Deaf, and the Captioned Media Program do not endorse the sites and are not responsible for their content.

• LATITUDE: THE ART AND SCIENCE OF FIFTEENTH-CENTURY NAVIGATION

http://www.ruf.rice.edu/~feegi/index.html

This site has information about ships, the science of sailing, traditional sailing, navigation, maps, compasses, earth’s magnetism, and much more. Each area includes links to additional resources.

• LOOKLEARN&DO http://www.looklearnanddo.com/documents/lunch_lake_project.html

One of the many projects on this site is building a sailboat. It includes simple instructions for elementary students as well as colored drawings showing the process.

• WHY DOES AN ICE CUBE FLOAT?

http://www.nyu.edu/pages/mathmol/modules/water/density_exp.html

This is an interactive site for a single science experiment. It includes predictions, density, and temperature, plus instructions and supporting photographs for completing the experiment.