Classroom Teacher Preparation
Physics 17: Density - How to Float a Concrete Canoe
Please use the following to prepare for the next SfS lesson.
Description:
The concepts of density and buoyancy are explained with several compelling demonstrations. Students then construct
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boats out of aluminum foil. Younger (4 -5 grade) students measure how much mass their boats can support before
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sinking; older (6 -8 grade) students also calculate the predicted capacity of their boats, and then test them in order to
compare their prediction to the actual maximum load.
Lesson Objectives – SWBAT (“Students Will Be Able To…”):
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4 -8
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Understand that density is mass divided by volume
Explain what makes something float
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6 -8
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Understand how to calculate the density of an object
Explain the relationship between buoyancy and density
Preparation:
This lesson is an introduction to the topic.
Vocabulary:
Introduce these terms:
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matter – anything that takes up space and has mass
These terms will be defined in lesson:
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mass – the amount of matter in something
volume – how much space a given mass occupies
density – mass divided by volume, i.e., how much mass is contained in a given volume
buoyancy – the ability of an object to float in a (liquid or gaseous) fluid
Room Set Up for Activities:
Students will work in pairs or groups of three to form boats out of aluminum foil and then test the maximum load the boat
can support. They will need one or two desks’ worth of space. Water is used, so their desks should be cleared of anything
that can’t get wet.
Safety:
There are no safety issues with this lesson.
Science from Scientists
617-314-7773 • [email protected] • www.sciencefromscientists.org
Copyright © 2016 Science from Scientists
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Related Modules:
This lesson may be taught as part of a sequence or group of related modules on Chemistry or Physics, particularly
Motion. Other modules in these sequences include:
Chemistry 2: Chemical Identification - A single chemical may be able to take on many forms, rendering simple methods of
identification such as sight ineffective. Chemists (your students) therefore use a multitude of tests to compare the
properties of a sample to known values in order to identify an unknown material. (Indirectly related)
Chemistry 4: Separation of Substances - After an introduction to elements, compounds, and mixtures, common methods
and reasons for separating mixtures are discussed. Students then design and implement a multi-step purification process,
the effectiveness of which is gauged by calculating the recovered fraction of components.
Physics 4: Gravity - This exploration-driven lesson uses an interactive physical model of a gravity well to introduce
students to the laws governing the gravitational interactions of objects.
For other module sequences and groups, look here: www.sciencefromscientists.org/sequences
Standards Covered:
Please click the following link to our website to review the standards covered by this lesson, listed by state:
http://www.sciencefromscientists.org/standards/
Lessons are matched to both national NGSS and local state standards.
Classroom Post and Activities:
A link to the Follow Up Student activity can be found in the Classroom Post on our website at
sciencefromscientists.org/cohorts. Use the name of your school/cohort and password to log in. Students make raisins
"dance" in a glass of soda.
Additional Resources:
WGBH Videos and Activities: The PBS educational site is a great, free resource for educators but you must create an
account to use the materials. The first time you log in to the PBS Learning Media website you will be asked to create an
account and provide an email and password. Once you have logged in, select “keep me logged in” to avoid having to
repeat the process.
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Comparing the densities of liquids, solids and gases:
http://mass.pbslearningmedia.org/resource/phy03.sci.phys.matter.lp_density/comparing-the-density-of-liquidssolids-and-gases/
Engineering challenge: Build a clay boat
https://www.teachengineering.org/view_activity.php?url=collection/duk_/activities/duk_float_mary_act/duk_float_m
ary_act.xml
Make a density column: http://scifun.chem.wisc.edu/HomeExpts/layeredliquids.htm
Dancing raisins: http://scifun.chem.wisc.edu/HomeExpts/dancingraisins.htm
Science from Scientists
617-314-7773 • [email protected] • www.sciencefromscientists.org
Copyright © 2016 Science from Scientists
Page 2