Introduction – Structural Engineering
Structural engineering is a field of engineering dealing with the
analysis and design of structures that support or resist loads.
Structural engineers are most often involved in designing buildings
and other large structures such as bridges. When structural
engineers develop their plans, they must take into account safety,
performance, as well as the cost of materials used.
In this unit, we have included activities that will simulate what
structural engineers do on a small scale. In almost all of the
activities, the students must not only consider how sound the
structure is but also how many resources are needed for building
the structure. Students will build earthquake-proof structures,
bridges out of straws, and domes out of gumdrops. The students
will test various parameters of each structure they build, such as
how fast a marble can roll through their foam roller coaster and
how long they can make their Popsicle stick structure last through
an earthquake. These activities will help the students understand
the many factors structural engineers must analyze and evaluate in
order to build a successful structure.
Grade Level:
All
Activity – Marble Roller Coaster
Introduction: In this activity, students will use pipe insulation to
build roller coasters for marbles to travel on.
Key Scientific Terms: gravity and velocity
Learning Targets:
I can use the engineering design process to design and build
a model roller coaster.
I can explain how roller coasters work.
I can calculate the average speed of my roller coaster.
Materials:
For each group, you will need:
1) Pipe insulation (2 three-foot long tube half pipes)
2) Masking tape
3) Stopwatch
4) Calculator
5) Cup
6) Marble
7) Ruler
8) String
9) Marble Roller Coaster Handout
Introduction (5 mins):
1. Explain to the students that today they will be roller coaster
engineers and will need to use their design and engineering skills to
build a roller coaster that fits a certain criteria using only the
materials provided.
2. Review the goal of today’s activity (to make the fastest roller
coaster).
3. Review definitions of design and engineer through the following
questions:
Can you recall what types of things an engineer works on? How does design relate to what engineers do?
Can you recall something that you designed?
Brainstorm and Design (10 mins):
4. Give each group their materials and the Marble Roller Coaster
Handout.
Grade Level:
All
Activity Time:
1 hour
Preparation Time:
5 minutes
Grouping:
2-3 students per
group
Activity – Marble Roller Coaster
5. Ask students to sketch a drawing of their roller coaster within their groups. Roller
coasters should include at least 2 hills and 1 loop (maybe modified for younger ages- i.e.
1 hill/1 loop, or just 2 hills).
6. As students are working as open ended questions about their designs.
How does your design work? Why did you decide to make your design that way? What things do you think will affect your design works?
Are there other ways to design this? Explain.
Build:
7. Once students have finished design of their roller coaster provide them with the
materials to build their roller coasters.
8. Instruct them to use their environments (i.e. desks, chairs, the floor) to build their
roller coasters.
9. Check in with groups throughout the building phase with these questions:
Can you describe the different parts of the roller coaster and their purpose? Predict how you think your roller coaster is going to work. Does this activity remind you of something else you have build or experienced?
Test:
10. When they have finished building their roller coaster, have them test out the
worksheet. They will need to do the following:
a. Time how long the marble takes from the start of the roller coaster to the end.
Take a total of 5 time trials.
b. Find the average of the 5 time trials.
c. Figure out how far the marble traveled, by measuring the tubing they have been
given.
d. Use the average time and the distance traveled to calculate the average speed of
the marble.
e. Make a drawing/diagram of their marble roller coaster and label specific points.
Reflection and Discussion:
11. Once students have completed challenge, spend some time discussing the roller coaster
design/engineering process. Some possible discussion questions include:
Which designs worked best and why? What elements from other roller coasters could be combined with your design to
improve it?
What other types of engineers and careers do you think are involved in the process or designing and building a roller coaster?
Redesign (if time allots)
Activity – Marble Roller Coaster
12. Have students redesign their roller coasts to try to make the marble travel faster.
Have them incorporate their new understandings from the reflection and discussion.
Science Connection:
When the marble is at the top of a hill, gravity is the force that acts upon it to put it into
motion. Steeper and longer roller coaster hills will result in an increase in the marble’s
velocity, or speed.
Activity – Marble Roller Coaster
Today you will be a roller coaster engineer and will get to design your very own
marble roller coaster. Here are some guidelines for building your marble roller
coaster:
Your marble must not fall off until it gets to the end of the track.
The marble must land in the cup at the end of the run.
You may only use the materials provided (exception: if you need to, you may tape
your roller coaster to classroom furniture).
Challenge 1: Work with your team to build a roller coaster that has 2 hills (including the initial hill) and 1 vertical loop.
Sketch some ideas for how you might want your roller coaster to look:
Once you have completed your roller coaster answer the questions below:
Time Trial
Time the marble from start to finish five
different times. Start the time when the
marble is released at the beginning of your
track and end when it lands in the cup.
Trial Time (in seconds)
1
2
3
4
5
Activity – Marble Roller Coaster
Average Time: Calculate the Average Time.
A) Add all your trials:
+ + + + =
Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial Total
B) Take the Trial Total time and divide by the number of trials (5) to get the average:
÷ 5 =
Trial Total Average Time
Average Speed: Calculate the Average Speed of your marble.
A) How far did your marble travel?
Using a piece of string measure out the length of the track. Track Length
B) To calculate speed, you need the distance the marble traveled (the length of the track)
and the time it took to travel:
÷ =
Track Length Average Time Average Speed
Activity – Marble Roller Coaster
Diagram: Make a drawing of your roller coaster.
Label the highest point.
Label the point where the marble goes slowest.
Label the point where the marble goes fastest.
If you are finished with Challenge 1, you can move onto Challenge 2. You will have to
dismantle your previous roller coaster to make the next one.
Challenge 2: Join another team and combine your materials. Build a roller coaster that has
3 hills (including the initial hill) and 2 vertical loops.
Activity – Gumdrop Dome
Introduction: In this activity, students will use gumdrops and
toothpicks to build the structure that can hold the most weight.
Key Scientific Terms: compression and tension
Learning Targets:
I will be able to explain the engineering design process.
I will collaborate with my partner to design a structure.
Materials(per pair): 1) 50 toothpicks
2) 30 gumdrops
3) 1 paper plate
4) Gumdrop Dome handouts (optional)
5) Weights to test the strength of the dome structures (weights,
books, etc. Something that can hang from the structure)
Directions:
Introduction
1. Explain how forces can act differently on different shapes.
2. Have students make some simple shapes out of toothpicks
and gumdrops and test how strong they are. Have students make a
square and a triangle and then compare each ones’ strength. The
students should see that the triangle is the strongest.
3. Explain how and why dome structures are built the way they
are. Show some pictures of real domes. Make sure to include
pictures of geodesic domes (those built from a network of
triangles).
How would you describe the structures in the pictures? What types of shapes do you see in the pictures?
Give examples of some of your favorite structures that you have seen?
Brainstorm/Design
4. Introduce the challenge to the students. Explain to them
that they will be given 30 gumdrops and 50 toothpicks to build the
strongest dome that can hold the most weight.
5. In pairs, have the students brainstorm ideas about how they
might build their domes.
Grade Level:
All
Activity Time:
30 minutes
Preparation Time:
10 minutes
Grouping:
Pairs
Adapted from http://pbskids.org/zoom/activities/sci/gumdropdome.html
Activity – Gumdrop Dome
How could you apply what you have seen in structures to how you would build your dome?
Can you identify the different parts of your structure?
How does your design work? Why did you decide to make your design that way?
Build and Test
6. Pass out materials.
7. If the students seem stuck, pass out the Gumdrop Dome handout. Let students use
this handout as a resource guide.
8. Allow 30 minutes for students to design and build their domes.
9. Once finished, students can test the strength of their dome design by adding weights
until their structure fails (collapses).
What things do you think will affect how many weights your structure will hold?
What other materials would be helpful for building your structure?
What do you think will happen as you add more weights to your structure?
Reflection and Discussion
10. Once students have completed the challenge, spend some time discussing the design
process. Some possible discussion questions include:
Which structures held the most weights and why do you think so? How could you improve your design? What elements from other structures could be
combined to improve your structure? How would you apply what you learned to develop a structure using straw and
string?
Science Connection:
Trinagles are more stable shapes than squares. When you push down on a triangle the two
forces that act on it are balanced. Those two forces are compression and tension. In a
triangle, the compression in the two sides (as you push down on the point of a triangle) is
balanced by the tension in the piece along the bottom, which pulls the sides back together.
Activity – Gumdrop Dome
How to Build a Gumdrop Dome
Step 1
Build a pentagon with 5 gumdrops and 5
toothpicks. Lay it flat on the table.
Step 2
Build a triangle above each toothpick in
the pentagon. The triangles should stick
up into the air.
Connect the top gumdrops of each
triangle all the way around the pentagon.
Step 3
Stick one toothpick in the top of each
triangle. Lean the toothpicks together
towards the center and join them with a
gumdrop.
Test how strong this dome really is!
Use this basic structure to build an even bigger dome. Just make the base larger and
build the same triangle pattern all the way around. You can make it taller by adding
another row of triangles, too!
Activity – Building for the Big One
Introduction: In this activity, students will use limited materials to
build a structure on a type of simulated soil that can withstand an
“earthquake.”
Key Scientific Terms: center of gravity
Learning Targets:
I can work effectively as part of a team to brainstorm and
solve a problem.
I can describe the characteristics of a stable structure.
I can explain how soil type affects a building’s ability to
withstand an earthquake.
I understand the concept of limited resources and time
constraints.
Materials:
(per class) Rectangular pie pan or box lid (something that is large enough
to hold an 8in circular baking pan and to serve as the Shake Table)
Golf balls or similar balls
Stop watch
Playdough (2 containers)
Grape nuts (1 box)
Water
Oobleck (cornstarch and water)
Measuring cup
(per group) 20 popsicle sticks
1 roll of masking tape
1 golf ball
1 aluminum 8in circular baking pan
1 ruler
Several sheets of scratch paper and a pencil
Soil Types Handout
A set of Job Description Tags
Preparation:
Set up the Testing Zone by placing golf balls in a rectangular pie
Grade Level:
All
Activity Time:
1 hour
Preparation Time:
Grouping:
3-4 per group
*Adapted from: The Tech Museum of Innovation, San Jose, CA
Activity – Building for the Big One
pan to make the shake table. The structures built by students will be placed in a pie pan
on the shake table, which will be agitated back and forth for 15 seconds to simulate an
earthquake. Lay out the stop watch and paper towels (for cleanup).
The Shake Table
Directions:
Introduction:
1. Start a discussion about earthquakes.
Who has experienced an earthquake? What was it like?
What causes earthquakes?
What kind of damage can earthquakes cause? What can be done ahead of time
to reduce how much damage will take place?
2. Explain that the design challenge today is to build a structure that can withstand a
major earthquake using only a limited amount of materials.
3. Review definitions of design and engineer through the following questions:
Can you recall what types of things an engineer works on? How does design relate to what engineers do?
Can you recall something that you designed? 4. Explain the different careers involved in building an earthquake-proof structure.
Today the students will be taking on these roles.
The Geologist researches soil types by reading the Soil Types handout. Each
geologist will be given a different type of soil to work with. Based on that
information, he or she advises the architect and structural engineer on the
structure design. The geologist is the lead in the making of the soil inside of
the aluminum pan.
The Architect designs the structure based on the required specifications. He
or she works with the geologist to determine if the design will work with the
group’s specific soil type.
The Structural Engineer(s) builds the structure based on the architect’s design
and the geologist’s recommendations.
Brainstorm and Design:
5. Divide the students up into group of 3 or 4.
Activity – Building for the Big One
6. Pass out the Job Description Tags to each group and have each student in the group
take on one of the three roles (geologist, architect, or structural engineer). If there
are 4 students in the group, have two of the students be structural engineers.
7. Each team of students will be building their structure on a different type of soil and
will need to adapt their structure in order to be as stable as possible on that particular
type of soil.
8. Explain the following rules & specifications for their structures:
The structure can only be built with 20 popsicle sticks and masking tape
The structure must be at least 2 popsicle sticks tall
The structure must hold a person (represented by a golf ball) without shaking
them off or out of the structure
The base of their structure must fit into their aluminum baking pan
The structure must be able to withstand 15 seconds of shaking in the Testing
Zone without falling or collapsing.
9. Assign each group one of the four soil types (bedrock, alluvium, gravel, or landfill).
Provide all of the necessary materials listed below and pass out the Soil Types handout
to the geologist so they can research their particular type of soil.
Bedrock – fill a pie pan with Playdough
Alluvium – fill a pie pan with Grape Nuts and enough water to soak them, but not
to fill the pan
Gravel – fill a pie pan with dry Grape Nuts
Landfill – fill a pie pan with Oobleck (1 ½ cup of cornstarch + 1 cup of water)
10. Give students 5-10 minutes to brainstorm and design. During this period, the geologist
will research their group’s soil type and how to make the soil mixture. The architect
consults the geologist and draws up a design of the structure based on the required
specifications. The structural engineer plans ahead of time how he/she will construct
the structure.
Build and Test:
11. Give each group 15-20 minutes to build their structures.
12. Have all of the groups gather around the testing zone and call up each group to test
their structure. The entire group should participate in testing their structure.
Structures should be placed into their pan (filled with the correct soil type), placed
within the testing zone, and shaken for at least 15 seconds.
Reflection and Discussion:
13. Follow up the activity with a discussion using the following questions.
What issues did you consider when designing your structure?
Which structures held up the best? Why? What features did you incorporate
to make your structure more stable? What types of features affect building
stability?
Activity – Building for the Big One
Foundation, shear force, support/reinforcement, triangles, wide to narrow (wide at base, narrow at top), low center of mass. How does what the structure is built on affect how much damage it takes?
What design changes or modifications will you consider for your next design?
What determines the magnitude of an earthquake?
Magnitude is a measure of the amount of energy released during an earthquake. The force is proportional to the amount of the energy released. This force travels spherically away from the point where energy is released (the focus).
Redesign (if time permits):
14. Have each group re-design and build their structure to be more stable. Emphasize
learning from testing and using ideas other groups used that were effective during
testing.
15. After each group has finished redesigning their structure, test each structure again.
Make sure to highlight the improvements the second time around.
16. Lead a discussion on the engineering design process and explain that the design
challenge they just completed is an example of utilizing this process to solve a problem.
Variations on this lesson plan:
In addition to testing whether a structure is earthquake-proof, you can challenge students
to see if their structure holds up to a rainstorm (simulated by spraying water from a spray
bottle) and windstorm (simulated by blowing a hairdryer).
Science Connection:
Having a low center of gravity (the point at which all of the weight of an object appears
to be concentrated) is essential for building a stable structure. This translates to
creating a structure, which is bottom heavy (i.e., wide at the base and narrow at the top).
Activity – Building for the Big One
Bedrock is the solid unweathered
rock that makes up the Earth’s
crust. The Earth’s outermost
surface is called the crust. Bedrock
may be composed of various
elements from region to region.
There are three major groups of
bedrock: sedimentary, metamorphic,
and igneous, each made of different
sets of minerals.
Alluvium is young sediment—
freshly eroded rock particles
that have come off the hillside
and been carried by streams.
Alluvium is pounded and ground
into finer and finer grains each
time it moves downstream.
Alluvium is typically made up of
a variety of materials, including
fine particles of clay and larger
particles of sand and gravel.
Gravel is any loose rock that is at
least 2mm and no more than 75mm.
It can be a mixture of sand, clay,
and small pieces of rock. It is
sedimentary rock and usually found
where there is, or were, rivers,
lakes, and glaciers. It happens
where rocks have been weathered
by wind or water or eroded.
A landfill is a site for the
disposal of waste materials by
burial such that it will be
isolated from groundwater and
will not be in contact with air.
Under these conditions, trash
will not decompose much.
Unless landfills are stabilized,
these areas may experience
severe shaking in a large
earthquake.
Activity – Building for the Big One
Directions: Cut-out and laminate the cards below and then attach them to a lanyard.
Geologist
The Geologist in the group will research and create the
group’s soil type: bedrock, alluvium, gravel, or landfill.
Soil Recipes:
Bedrock = Playdough
Alluvium Pan = Grapenuts + enough water to soak
them, but not fill the pan
Gravel Pan = Dry Grapenuts
Land fill = Oobleck (1 ½ cups of cornstarch + 1 cup
water)
Architect
The Architect in the group will design a structure that
meets the following parameters:
Parameters:
Structures must be at least two Popsicle sticks tall.
Structures must hold a golf ball without shaking it out
of the structure.
Structures must fit in a pan.
Structures must be able to withstand 15 seconds of
shaking without falling or collapsing (on shake table).
Structural
Engineer
The Structural Engineer(s) will build the
structure using popsicle sticks and 2 hot glue
sticks. Their structure must be based on the
Architect’s design and the Geologist’s
recommendations.
Structural
Engineer
The Structural Engineer(s) will build the
structure using popsicle sticks and 2 hot glue
sticks. Their structure must be based on the
Architect’s design and the Geologist’s
recommendations.
Activity – Paper Structures
Introduction: In this activity, students will try and build the
strongest structure using a limited amount of paper.
Key Scientific Terms: center of gravity
Learning Targets:
I can collaborate with my group members and listen to each
other’s ideas to complete a challenge
I can explain how to manipulate paper to make it hold more
weight
I can describe the types of careers involved in designing and
building a structure
Materials:
(per group) 1) 30 sheets of 8½” X 11” color paper (Give each group a different
color, if possible.)
2) One roll of masking tape (per class) 3) A class set of textbooks
Introduction:
1. Introduce the activity to the students by asking them to
describe some of the tallest or unique buildings or structures that
they have ever seen.
2. Lead a discussion about the types of careers that could be
involved in the process of designing and building a structure or
building.
3. Tell them that today they will be structural engineers who must
design and build the strongest structure using a limited amount of
paper and time. Their challenge is to build a structure at least 6
inches high which can support a book. They will have 5 minutes and
30 sheets of paper. They may not tape the structure to a table or
any other fixed structure.
Brainstorm:
4. Divide the class into teams.
5. Have each team brainstorm for 3 minutes possible designs for
their structures. As groups are brainstorming, ask open-ended
questions about their designs.
What types of designs do you think would be the strongest?
Grade Level:
All
Activity Time:
20 minutes
Grouping:
Groups of 2 – 3
*Adapted from SWE.org
Activity – Paper Structures
How can you manipulate paper to make it hold more weight?
Build and Test:
6. Give each team a stack of paper and a roll of masking tape. They will have 5 minutes to
build their structure.
7. Once the time is up, test each structure by placing a book on the structure. Continue
to add books until the structure collapses.
Reflection and Discussion:
8. Once students have completed the challenge, spend some time discussing which
structures worked the best and ways to improve their group’s structures. Use the
following questions to guide the discussion.
Which structure was strongest and why? How did having a time limit affect your end product? How would you redesign your structure?
Some ways you can make a structure more stable is by:
Making the base wider
Taper the structure (Make the top skinny and the base wide)
Make the base heavier
Lower the center of gravity. The center of gravity is the point at which all of the
weight of an object appears to be concentrated.
Add more support points
Science Connection:
Having a low center of gravity (the point at which all of the weight of an object
appears to be concentrated) is essential for building a stable structure. This
translates to creating a structure, which is bottom heavy (i.e., wide at the base and
narrow at the top).
Activity – Straw Bridges
Introduction: In this activity, students will design and build the
strongest bridge using only straws, tape, and paper clips.
Key Scientific Terms: force, compression, and tension
Learning Targets:
I can work with my teammates to build the strongest bridge.
I can work with available resources to complete a challenge.
I can explain how engineers have to design structures using
limited resources (materials, money, manpower, and time).
Materials:
(per group) 25 straws
5” of tape
15 paper clips
Small weights
Directions:
Introduction:
1. Introduce the challenge to the youth. Imagine you are a
structural engineer and must design and build the strongest bridge
using the available resources. The goal of this activity it to build a
bridge that can hold the most weights before breaking.
2. Lead a discussion about how and why bridges are built the
way they are. Show pictures of real bridges or have students recall
how different bridges they have seen look like.
Describe what you notice about the various bridges in the pictures or bridges that you have seen
What are things that you think affect how strong a bridge is?
What types of careers are involved in designing and building a bridge?
Brainstorm and Design
3. Give each group their materials.
4. Have each group brainstorm possible designs for their
bridge using the available materials.
Grade Level:
All
Activity Time:
15 minutes
Preparation Time:
None
Activity – Straw Bridges
5. Have each group sketch out their design on a sheet of paper. As they are working, ask
them open ended questions about their design.
Summarize the parts of your design Have you ever done anything like this before?
Build:
6. Give each group 15 minutes to construct their bridge. As they are building, ask open-
ended questions about the design.
What are the different parts of your bridge and what is their purpose? How many weights do you think your bridge will hold and why?
What do you think will happen as we add weights to your bridge? What part do you think will begin to collapse first?
Test:
7. After all the groups have finished building their bridges, test the strength of each
bridge by placing one weight at a time until the bridge collapses. Record the number of
weights each group’s bridge can hold on a white board or chart paper.
Reflection and Discussion:
8. Follow up the activity with a discussion using the following questions.
What elements would you change about your design and why? Suppose you could choose one additional material to use, what material would
you choose and why?
What was the most challenging aspect of this design challenge? How did you overcome this challenge?
Redesign:
9. If time permits, allow each group to go back and redesign their bridge. Emphasize
learning from testing and using ideas other groups used that were effective during
testing.
10. After each group has finished redesigning their bridge, test each bridge again. Make
sure to highlight the improvements the second time around. Record the number of
weights each group’s bridge can hold on a white board or chart paper.
11. Lead a discussion on the engineering design process and explain that the design
challenge they just completed is an example of utilizing this process to solve a problem.
Activity – Straw Bridges
What approach would you use to design the tallest structure using the same materials?
How do engineers work together to solve a problem? Defend the need for a process like the engineering design process to solve problems and design new products.
Science Connection:
The design of a bridge affects the amount of force that you can place on the bridge. Two
forces that every bridge has are tension and compression. Compression occurs when
something is being squeezed together. For example, as you sit in a chair, the legs of the
chair are experiencing compression because they are being squeezed between you and the
floor. Tension occurs when something is being pulled apart. A rope in a tug-o-war
experiences tension.
Handout – Engineering Design Process
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