How Did They Do It?
To learn what levers are and how they might have been used by the ancient
Egyptians in building their monuments. To learn what center of gravity is, how
to determine the center of gravity of asymmetrical objects, and how this
knowledge might have helped the Egyptians in building their monuments.
- To acquaint students with the construction challenge, have them review the
summary for Obelisk.
- You may want to have students view the
Obelisk video to further
acquaint them with the challenges of raising a multi-ton obelisk. (The video
can be purchased as part of the Secrets of Lost Empires set or individually.
Allow a week for shipping.)
- Now familiarize students with the concept of levers. Print out the
Loads Activity and have students conduct both parts of the activity. Once it is available (Week of March 15) have students do the Lever an Obelisk online activity to further investigate the principle of
- You may also want to familiarize students with the concept of center of
gravity. You can print out and use The Great Trilithon Balancing Act
Activity, which demonstrates how locate an object's center of gravity using
a cardboard trilithon.
- As students are learning about these concepts, have them follow the
expedition's progress by reading recent dispatches.
Use these dispatches to discuss how the concepts students are learning are
involved in the raising of the obelisk. (Note: Dispatches are expected to be
posted every two days.)
- Have students develop a poster or model of how they would raise the obelisk.
The poster should outline how each science concept comes into play at different
points in the process. Students' concepts will differ depending on which method
they choose to use. For example, if they use a pulley they might point out the
concept of mechanical advantage or if they use a lever, they might point out
fulcrum and load points.
- After performing the suggested activities, students should evaluate the
suitability of using levers to move large masses of stone to build buildings or
lift monuments such as obelisks. Would a lever have worked to lift the obelisk?
What kind of lever? What might be some disadvantages to using a lever to raise
- For another version of this activity, check out Lever Loads Activity II.
National Science Education Standards
Content Standard E: Science and Technology
Abilities of technological design
Evaluate completed technological designs or products
Students should use criteria relevant to the original purpose or need,
consider a variety of factors that might affect acceptability and suitability
for intended users or beneficiaries, and develop measures of quality with
respect to such criteria and factors; they should also suggest improvements
and, for their own products, try proposed modifications.
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