Zip Line
1. Title of the Lesson: Zip Line
2. NJ Core Curriculum Content Standards addressed in the lesson.
 5.1.12.C.1 (Refinement of understandings, explanations, and models occurs as new
evidence is incorporated): Reflect on and revise understandings as new evidence
emerges.
 5.1.12.D.1 (Science involves practicing productive social interactions with peers, such as
partner talk, whole-group discussions, and small-group work): Engage in multiple forms
of discussion in order to process, make sense of, and learn from others' ideas,
observations, and experiences.
 5.2.C (Forms of Energy): Knowing the characteristics of familiar forms of energy,
including potential and kinetic energy, is useful in coming to the understanding that, for
the most part, the natural world can be explained and is predictable.
 5.2.D (Energy Transfer and Conservation): The conservation of energy can be
demonstrated by keeping track of familiar forms of energy as they are transferred from
one object to another.
 5.2.12.D.1 (The potential energy of an object on Earth's surface is increased when the
object's position is changed from one closer to Earth's surface to one farther from Earth's
surface.): Model the relationship between the height of an object and its potential energy.
 5.2.12.D.4 (Energy may be transferred from one object to another during collisions.):
Measure quantitatively the energy transferred between objects during a collision.
 5.2.E (Forces and Motion): It takes energy to change the motion of objects. The energy
change is understood in terms of forces.
 5.2.12.E.1 (The motion of an object can be described by its position and velocity as
functions of time and by its average speed and average acceleration during intervals of
time.): Compare the calculated and measured speed, average speed, and acceleration of
an object in motion, and account for differences that may exist between calculated and
measured values.
 5.2.12.E.2 (Objects undergo different kinds of motion (translational, rotational, and
vibrational).): Compare the translational and rotational motions of a thrown object and
potential applications of this understanding.
 5.2.12.E.3 (The motion of an object changes only when a net force is applied.): Create
simple models to demonstrate the benefits of seat belts using Newton's first law of motion.
3. Identify Resources needed. (identify texts, equipment, media, family or community resources
to be used in the lesson).
a. Teacher Use: Targets
b. Student Use: Marble, string, paper cup, paper clip, index card, tape, scissors, chairs or
other objects to use as anchors for the zip line
4. Describe what students should know before they start the lesson.
 Students should be able to work cooperatively in small groups. They should listen to and
have respect for others' ideas.
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Students should understand the steps involved in the engineering design process.
Although this lesson handout gives extensive scaffolding assistance to students who are
less familiar with the process, so this lesson could be used early in the year with students
who have less engineering experience.
This lesson doesn't require very much specific physics knowledge so it could be done
early in the year as part of the mechanics unit. It could also introduce the unit on torque
and rotational motion.
5. State the objectives of the lesson.
 Students will increase their ability to work cooperatively to solve a problem.
 Students will learn how to use a systematic approach to solving a problem.
 Students will learn about torque and how it relates to zipline design. (Some groups will
have cup rotate to deliver marble to target.)
 Students will learn how to use the engineering design process to solve a problem.
 Students will learn that engineering involves using their ideas and knowledge to solve
real-world problems.
 Students will learn about different types of engineering (designing structures such as the
zipline), but also that other engineers are responsible for developing stronger, cheaper, or
more environmentally friendly construction materials. Students will learn how the work
done by engineers affects society for the better.
 Students will apply their knowledge of physics to solve a real world problem.
6. Identify important ideas in terms the subject area - describe in detail. Real life connections
(make a list).
 The engineering problem-solving strategy (which mimics the ISLE cycle for
experimentation) involves devising a series of possibilities that are tested and revised.
 Many different types of engineers work together on a single project.
 The eight steps of the engineering design process are: identify the need or problem,
research the need or problem, develop possible solutions, select the best possible
solution, draw a prototype, test & evaluate, communicate the solution, and redesign.
 The engineering design process includes constructing a physical prototype: starting with
plans and ideas, using materials to build the physical model. This prototype can then be
tested, and the results applied to redesign and improve.
 Torque: Sum of (force * radius from pivot point). For an object to be stable, not only
must the sum of the forces exerted on it be zero, but the sum of the torques exerted on it
must also be zero. When the net torque exerted on an object is not zero, the object will
experience rotational acceleration.
 Projectile Motion: If the marble is moving down the zipline with a certain velocity, it will
maintain that velocity unless the net force exerted on it is not zero. The magnitude and
direction of velocity and net force determine where the marble will land.
7. Describe potential difficulties students may experience with the content. Describe all
formative assessments that you plan to use and how you will provide feedback.
 Students may have difficulty working cooperatively. One group member may dominate,
especially boys in mixed gender groups.
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Students may have difficulty applying the engineering design process, rather than just
employing a trial and error strategy. I will remind the students to plan ahead. Also, I can
present the problem but not make the materials available for the first five minutes, which
will force students to plan (steps 2-5) before building their prototype.
I will monitor the groups, and make sure to engage group members whose opinions don't
appear to be being listened to. This will demonstrate to the dominating group members
that the others' ideas are to be valued. This also will ensure that all group members are
contributing equally, and that all group members understand the successes and failures of
their prototypes.
Students may have difficulty determining why their prototype isn't working. I will ask
groups what problems they are having, or what is standing in the way of their meeting
their goals, to engage them in a discussion about the possible strategies they could
employ to solve their problems, rather than just using trial and error. Students may need
to be prompted to systematically change one aspect of their design at a time to solve the
problem. I will ask students what assumptions they made in their initial plan that turned
out to not be valid, and how they have revised their assumptions.
If a group adopts a new approach, I will ask them to explain what they changed and the
reason for the change. In addition, I will try to get them thinking about the physics
explanation for the failure of their prior prototype.
This lesson can be very frustrating because unlike other lessons where most student
groups “succeed” but with prototypes that just have lower performance than other groups
(launch object shorter distance, support less weight on bridge, etc), some groups may
struggle to get the marble to ever hit the target. The teacher may need to provide extra
assistance to enable these groups to get past their sticking point and achieve success.
8. Provide a description of the lesson including an agenda for the lesson.
 See handout attached at end of lesson plan
9. Time Table – who is going to be doing what and when during the lesson to make sure that
students are actively engaged.
Clock reading
“Title of the
Students doing
Me doing
during the lesson
activity”
0 – 3 minutes
Introduction
Listening
Talking
3 – 10 minutes
Planning
Planning, brainstorming,
Listening, monitoring
discussing ideas
student group work
10 -35 minutes
Construction
Constructing the prototype Monitoring student work
& Testing
zipline, testing &
redesigning
35 – 40 minutes Testing
Testing ziplines,
Supervising testing
Observing Peers' Testing
procedure
40 – 45 minutes Reflection
Talking
Listening, summarizing
10. Describe the homework you will assign. What guidance will you provide the students?
 The homework will be for students to assess the strengths and weaknesses of their own
design, and also that of at least one other group. and make at least one suggestion for a
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modification they could make that would meet a different need/ solve a different
problem. This engages the students in the engineering design process. Discuss the
homework the next day so students can learn from the ideas of others. Students will be
instructed to think about how real world engineers apply the engineering design process,
and which types of engineers might work together on the project. Students will be
challenged to think of real-world situations that are similar to this project, where
engineers are asked to design a product to deliver an object to a specific location.
11. Teacher's Guide
 As this lesson would most likely take place early in the school year when students are
less familiar with the engineering design process, this lesson is scaffolded to assist
students with the steps in the process. For example, the questions on the first page of the
handout prompt students to think about steps 3-6 in the design process, and the second
page reminds students that they should have multiple entries for these steps. If this lesson
is used later in the year or with students who are familiar with the engineering design
process, the handout could be modified to remove this scaffolding.
 Make sure students are divided into effective groups. Group together students with
differing strengths. Make sure all group members are actively participating.
 Make sure students follow the engineering design process and plan before building.
 Ensure that you are familiar with the materials and their benefits/ pitfalls.
 With the homework, make sure students think about how many different types of
engineers might try to improve the zip line. Materials cost? More environmentally
friendly materials? Accuracy/ reliability enhancement? And so on. Students will be
challenged to think of real-world situations that are similar to this project, where
engineers are asked to design a product to deliver an object to a specific location. This
can include anything from vending machines to military equipment to assembly line
robots. What are the requirements for accuracy and repeatability in these different
situations? Make sure a full class discussion of the homework assignment is included in a
subsequent class period.
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Zip Line
Goal: Design and build a structure that will carry a marble down a zip line and deliver it to the
target, following the criteria listed below.
Design Criteria:
 You will be given 9 feet of string. You must set up a 6 foot long zip line, where one end is
approximately 20” higher than the other end.
 Only materials listed below may be used.
Available materials:
Material
Quantity Allowed
String
9 feet
Paper Cup
1
Index Card
1
Paper Clip
1
Tape
Unlimited
Questions to ponder and answer:
1) How can you design the structure so that it carries the marble down the zip line? What are the
possibilities? What are the advantages and disadvantages to each? How did you decide
which one to select? Did you change your design after testing your initial prototype, and
if so, why?
2) How can you attach the marble-carrier to the zip line? What are the options? What are the
advantages and disadvantages of each? How did you decide which one to select? Did you
change your design after testing your initial prototype, and if so, why?
3) How will you get the marble-carrier to release the marble so it hits the target? What are the
possibilities? What are the advantages and disadvantages of each method? How did you
decide which one to select? Did you change your design after testing your initial
prototype, and if so, why?
4) Is accuracy (how close the marble lands to the center of the target) or reliability (in what
fraction of the attempts does the marble hit the target) more important in your design?
Give examples of real-world situations where accuracy is more important, and where
reliability is more important.
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Be sure to follow the Engineering Design Process and document your work. You should have multiple entries
in steps 3 through 6 as you continue to test and redesign. This is what engineers do! Failure of a prototype is
not a bad thing, rather it allows engineers to apply what they have learned as they redesign.
Step Number
1: Identify the need or problem
2: Research the need or problem
3: Develop possible solutions
4: Select the best possible solution
5: Draw a prototype
6: Test and evaluate
7: Communicate the solution
8: Redesign
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Comments and Observations