Lesson Plan Index
What Floats Your Boats?

 What Floats Your Boats? - by Viki Babcock (middle/high school science) The problems of wartime often require creative solutions. The Battle of D-Day was no exception. This activity has students learning about some of those historical innovations and designing their own creations, while at the same time learning about buoyancy and Archimedes' Principle.
Estimated class time

2 to 3 class periods

Lesson Objectives

Students will:
• Understand the concepts of buoyancy and Archimedes' Principle.

• Learn about creative solutions to tough problems.

• Design and create their own flotation device.

• Compare dimensions of a model to the real thing to determine scale.

• Analyze experimental results and suggest improvements.
Materials needed

• A copy of the SECRETS OF THE DEAD: "D-Day" video. (For ordering information, visit Shop PBS for Teachers)

• TV and VCR/DVD

• Internet access

• Copies of "D-Day: Viewer's Guide"

• Copies of "What Floats Your Boats? Data Table and Analysis Worksheet"

• Video clips are available on the SECRETS OF THE DEAD: D-Day website, but if you wish to purchase the complete program, visit PBS Shop for Teachers http://shop.pbs.org/teachers/products/SEDE744

• A set of weighted tanks (These can be plastic or metal toy tanks weighted with fishing weights, ball bearings, lead weights, or other substances. Have at least three different weights for the tanks, ranging from a few ounces up to a pound or two. Have students construct the weighted tanks as a preliminary activity, if desired. OR, use other weight samples to represent the tanks.)

• Variety of materials to create floating devices: aluminum foil, wax paper, popsicle sticks, modeling clay, plastic wrap, balloons, glue gun, twine, etc.

• Balance or scale

• Two basins or plastic tubs, one larger than the other

• Water

• Calculators
Teaching Strategy

 Teachers! Video clips for your students are available here. Video Clips
Day one:
1. Ask students to explain the meaning of the phrase "Necessity is the mother of invention." Discuss in class how this applies to technology development. Then direct students to the Secrets of Dead: D-Day Web site at http://www.pbs.org/wnet/secrets/
case_dday/index.html
. Read the "Background" and "Clues and Evidence" sections individually or as a class. Discuss. Allow students to investigate Hitler's D-Day Defenses interactive.

2. Option 1: View video clips 1 through 6 on the site http://www.pbs.org/wnet/secrets/
lessons/lp_dday_videos.html
and either discuss the questions in class or have students individually record their answers.

3. Or Option 2: Introduce the video by discussing how the problems of war often lead to scientific innovations. Show the first part of the SECRETS OF THE DEAD: D-Day video from the beginning to approximately 00:27:30 when the narrator states that the "landing was scheduled to take place on June 5, 1944." Have students take notes or answer the questions on the viewer's guide. Discuss responses.
Day two (and three, if necessary):
1.  Interactive Hitler's D-Day Defenses After completing the interactive for this episode students should answer these questions.
Encourage students to learn more about Archimedes' principle and buoyancy. Direct them to the interactive activity at Buoyancy Brainteasers at http://www.pbs.org/wgbh/nova/lasalle/buoyancy.html, as well as exploring other sites on the topic (see Internet Resources.)

2. Refer students to video clip 3 from option 1 or to question 7 of the Viewer's Guide from option 2. Inform students that they will be asked to learn about Archimedes' principle and then put that knowledge to use, just as it was done while designing the DD tank.

3. Challenge the students to design and construct their own device capable of floating the weighted tanks. Divide the students into small groups of 2 to 3 students each. Have materials on hand for students to use to create their own "tank-boat" which hopefully will stay afloat while holding each of the weighted tanks. Teachers may want to have the teams present their design plans before distributing materials. OR students could plan their boats during one class period and bring in their own materials the next day.

4. Using the Data Table and Analysis Worksheet, each team should record the mass of their boats before they test it with the various weighted "tanks." Test the boats by placing one of the tanks in the boat and putting the whole thing in a basin filled to the very top with water. The filled basin should be placed in a larger tub in order to catch any water that overflows. Before testing the device with another tank, be sure to refill the basin.

5. Using a graduated cylinder, measure and record the amount of water displaced by the boat. Also record whether the boat sank or floated. Complete the rest of the data worksheet.

Internet Resources

Assessments

• Written responses to Viewer's Guide questions, or participation in discussion.

• Participation in group's design and data collection

• Responses to data table and Analysis worksheet
Extensions

• Watch the rest of the SECRETS OF THE DEAD: "D-Day" video to learn about more of the innovations created as a response to the D-Day problem.

• Research previous wars for innovative machinery. Display findings in a timeline.

• Design a machine that might be useful in a current or perhaps future war.
Correlation to National Standards

Correlation to National Science Standards from http://bob.nap.edu/html/nses/html/6e.html#csc912

CONTENT STANDARD E: As a result of activities in grades 9-12, all students should develop abilities of technological design:
• Students should demonstrate thoughtful planning for a piece of technology or technique. Students should be introduced to the roles of models and simulations in these processes.
CONTENT STANDARD E: As a result of activities in grades 9-12, all students should develop understandings about science and technology:
• Science often advances with the introduction of new technologies. Solving technological problems often results in new scientific knowledge. New technologies often extend the current levels of scientific understanding and introduce new areas of research.

• Creativity, imagination, and a good knowledge base are all required in the work of science and engineering.
Correlation to National Math Standards from http://standards.nctm.org/document/chapter7/meas.htm

Measurement Standard for Grades 9-12: In grades 9-12 all students should make decisions about units and scales that are appropriate for problem situations involving measurement.

Number and Operations Standard for Grades 9-12: In grades 9-12 all students should judge the reasonableness of numerical computations and their results.