Lesson: Target Ball Drop (Application Exp.)
1. NJ standards addressed in the lesson:
5.1.12.B.1:Design investigations, collect evidence, analyze data, and evaluate
evidence to determine measures of central tendencies, causal/correlational
relationships, and anomalous data.
In creating their ball drop, students will come across many obstacles that they did not
account for in their original design. Students will have to think about the problems they are
having and what assumptions they were making that turned out to not be trivial.
5.1.12.B.3: Revise predictions and explanations using evidence, and connect
explanations/arguments to established scientific knowledge, models, and
theories.
AND
5.1.12.C.1: Reflect on and revise understandings as new evidence emerges.
AND
5.1.12.C.2: Use data representations and new models to revise predictions and
explanations.
This experiment requires a great deal of design and redesign (especially the later part). In
doing so, students will represent new design ideas in diagrams before redesigning in order
to eliminate the “trial and error” approach.
5.1.12.C.3: Consider alternative theories to interpret and evaluate evidence-based
arguments.
If the outcome of the experiment does not meet expectations, reevaluate assumptions and
revise explanations as part of the engineering redesign process to solve the problems that
arose and complete the task successfully.
5.1.12.D.1: Engage in multiple forms of discussion in order to process, make sense
of, and learn from others’ ideas, observations, and experiences.
AND
8.1.12.C.1: Develop an innovative solution to a complex, local or global problem or
issue in collaboration with peers and experts, and present ideas for feedback in an
online community.
Students will work together in groups (if possible containing individuals of various
strengths and backgrounds) to collectively solve the problem at hand and each contribute
their own knowledge and ability.
5.2.12.E.1: 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.
Using friction and kinematic equations, students should be able to calculate the velocity of
the ball as it is released and therefore attempt to calculate the optimal drop point for the
ball. In most cases, this will turn out to be incorrect. It is important for students to
understand the assumptions they made in their calculations and revise models and
calculations to try to account for the assumptions that were perhaps a little weak.
2. What students should know before they start the lesson:

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
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Basic kinematic equations
Projectile motion
Friction
Steps of the engineering design process
Gravitation
3. Goals of the lesson
Content:
Goals
Standards Addressed
Projectile motion and kinematics
5.1.12.E.1
Friction
5.1.12.E.1
Types of engineers
8.1.12.C.1, 5.1.12.D.2
Process:
Goals
Standards Addressed
Understand parts of the Engineering Design Process
8.1.12.C.1, 5.1.12.D.2
Conduct an application experiment
5.1.12.C.1, 5.1.12.C.3
Systematically make small changes when problems arise
5.1.12.C.3
Epistemological:
Goals
Standards Addressed
Understand why a given solution does not work and come up
with solutions.
5.2.12.E.1, 5.1.12.C.1,
5.1.12.C.3
Analyze what assumptions were made and how they affect
results
5.2.12.E.1, 5.1.12.C.1,
5.1.12.C.3
Learn to appreciate and use others’ abilities and cooperate to
achieve a common goal
5.1.12.D.1, 8.1.12.C.1
Types of engineers necessary for a mission as explained in the
handout.
5.2.12.E.1, 5.1.12.D.1,
8.1.12.C.1
Metacognitive:
Goals
Standards Addressed
How can I contribute my strengths to the discussion and help
solve the problem?
5.1.12.D.1, 8.1.12.C.1
4. Most important ideas

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Aspects of the engineering process: Identify the problem, research the problem (mathematical
approach), develop possible solution, construct prototype, test and evaluate,
Redesign/communicate solution.
Evaluating assumptions and application of theory is not always straight forward.
Addressing problems with design one at a time, not all together
Types of engineers involved in space programs
5. Student potential difficulties:

Understanding why outcome did not match predicted values from mathematical
calculations.
 This is the perfect example of evaluating assumptions. The situation that the students are
dealing with contains many different moving parts, the effects of which cannot always be
accounted for. For example, if the string bounces while the cup is sliding, this will make
the final vel. lower than expected. Although students cannot account for this difference
mathematically, they can note it in the design process and explain how they will overcome
the obstacle.

The actual construction and design process.
 Students need to be reminded of the type of difficulties actual engineers have with
construction. Sometimes designs need to be reevaluated if the initial design does not work
out as planned and sacrifices may have to be made in design or construction in order to
achieve something similar to the original design.
ex:
“What is standing in the way of you succeeding with your original design?”
“What problems are you experiencing? How can you overcome each problem
individually?”
“Now that you know your system works, can you make any changes to make it more
consistent or better? More accurate?”
6. Equipment needed:
Student Use
 String (Fishing wire or kite string preferable).
 Paper or plastic cup
 Marble
 Paper Clip
 Index card
 Tape
 Paper target
Teacher use
 Measuring tape
7. Lesson description:
Catapult Design(testing experiment)
Lab Goals:
 Accounting for sources of challenges in design
 Learn to redesign without trial and error
 Types of engineering involved in Space travel
The story:
In an effort to verify if there is any water on the moon, NASA wants to drop a piece of the
rocket that will carry the LCROSS probe up to the moon onto the surface. The 2.4 ton piece will
strike the surface of the moon at 1.6 mi/sec. This collision will throw up a dust cloud 6 miles high.
The LCROSS probe will then collect samples from the plume and send the information back to earth
for analysis. (http://www.foxnews.com/scitech/2009/10/07/nasa-crash-probe-moon-water)
Before completing the task, NASA needs to get an idea of the trajectory that the rocket piece
will take. This is where you come in. Using a specific setup (calculated by NASA mathematicians to
model the specific conditions of the actual probe), you will attempt to make a device to accurately
drop a marble onto a target.
Design Criteria:
You are limited to the following materials:
 9 ft. of string
 1 marble
 1 (plastic/paper) cup
 1 index card
 1 paper clip
 Masking tape
The string used to model the flight trajectory of the probe before the drop should be 6 ft. long and
one end must be 2 ft. above the other (See picture below)
Procedure: Follow the steps below and fill in the corresponding sections in the
Engineering/Design Process handout.
a) Before starting your design, you need to find the conditions of the launch. Using what we
know about mass, gravity, friction, and projectile motion, find vox of the marble towards the
bottom of the string. Attempt to predict where you will need to release the marble in order
for it to hit the target.
b) After doing your preliminary calculations, begin brainstorming designs.
c) Decide on the best method and make sure to describe and sketch your design.
Design Process Handout
Step
Notes
1) Problem:
Calculations of
necessary initial x
velocity to hit the
target.
2) Research/Possible
Soln’s: Describe
your ideas and
methods..
3) Best Possible Soln:
Sketch final design
(specifically how
the cup will release
marble onto target)
4) Soln. design
features: Describe
design features.
Include how this
design will achieve
necessary predicted
initial velocity.
5) Construct, test,
and evaluate: note
and changes made
during construction
here. Did the ball
hit the target?
6) Communicate
Solution: If original
design did not
work, explain why.
What assumptions
did you make in
calculations? Note
all changes made to
original design.
7) Redesign: Draw
your final product
with all
measurements.
Teacher Notes:
It is crucial in this assignment that students learn to think of the assumptions they use as the
basis of their knowledge. There are many variables that can affect the final result in this situation, so
simple calculations made with kinematics will most likely not be able to account for all the variation
occurring. Students don’t need to calculate the variations, but having students analyze their
assumptions and make changes to their design based on these assumptions is a step in the right
direction.
It is very easy for students to approach this lab from a “trial and error” perspective. In order
to truly drive home the “design” process, it is the teacher’s job to encourage students to try to plan and
reason as much as possible. Rather than let the futz around, try to get the reasoning out of them and
have them realize what changes will be most effective in helping them drop the ball on the target. In
addition, students need to realize that when there is a problem that needs to be addressed, one should
try to make small changes to singular problems than one change to many problems or, even worse,
decide that nothing works, take it apart, and rebuild it. Addressing problems systematically is
beneficial to the engineering process and their final goal.
NASA, as a company, employs the use of many different types of engineers. As such, this lab is a
good forum for discussion on the types of engineers necessary to make space travel possible. Some
types include:
 Aerospace engineers (obviously)
 Food/chemical engineers: Freeze drying food and production of food for space travel
 Biomedical engineers: Healthcare apparatuses to be used by the astronauts
 Chemical engineers: Fuel production and analysis
 Bio engineers: analysis of organic materials.
 Civil/Mechanical engineers: construction of launching pads and auxiliary structures
 Electrical engineers: Wiring in the probes and rockets.
 Many more.
It is possible that some students will be faster than others in the completion of the task. In this
scenario it is good to have some ideas to make the task more challenging or to have some extra
materials and require that they be added to the design.

If the design is hand operated (a student physically pulls or pushes something) to
complete the task, have them make it fully automated.
 If the design is not always consistent, but works sometimes, have them make it more
consistent.
 Have students incorporate more materials:
o Rubber band
o Straw
o Popsicle stick
o Etc.
Finally, it is important for students to realize that completion of the task is not indicatory of
their grade on the assignment. Their grade will depend on the rubrics for an application experiment
(which they will have access to from the teacher website). So it is their work and accurate analysis of
assumptions and proper reasoning of agreement or disagreement between predictions and outcomes
that will affect their grade for the assignment.
(If necessary to be completed in one day, have students do preliminary calculations for homework the
previous day. This can be done as a general problem without giving away the story. The following
Time Table will use this implementation)
8. Time Table(2 Day lab or 1 day extended period)
Clock reading
during the lesson
0 - 5 min
5-10 min
10-15 min
“Title of the
activity”
Homework quiz,
receive feedback
Introduction,
statement of story
and materials
Initial research and
calculations
15-40 min
Design and test
process
40-45 min
Discussion and
conclusion
Students Doing
Teacher Doing
Writing
Checking up equipment for
the first activity
Listening taking notes, Addressing class, showing
Getting into groups.
material
Discussing
calculations from
homework as applied
to the current task
Designing based on
calculations.
Redesigning if
necessary
Cleaning up materials
and discussing
outcome and
difficulties in design
process.
Listening to student
discussion and correcting
mistakes in calculations if
necessary.
Helping students overcome
design hurdles. (see
Possible students
difficulties)
Discussing design problems
and process with students.
Giving out homework.
9. Formative Assessments:
Content Goals:
 Correct method for calculating Projectile motion of marble
 Identifying engineers in homework
Process Goals:
 Detailed completion of the design handout
 Assessment through testing experiment rubrics
 Ability to overcome problems will demonstrate that they are able to address small
problems one at a time rather than tear the whole thing apart and start over.
Epistemological Goals:
 Students’ ability to accurately and effectively analyze assumptions and explain what effect
this had on the final design.
 Ability of students to effectively solve problems and hurdles in the design process.
 Students are able to effectively work in groups and no one individual is doing bulk of work.
 In homework, answers question relating engineering and physics effectively.
Metacognitive Goals:
 Ability to answer homework question on contribution to the team and design process.
10.
Modification for different learners:
By nature of the course, different learners will automatically be accounted for. Students will be
working in groups, so the activity is already a cooperative learning activity. The activity could
utilize technology in the form of graphing or mathematical programs for learners who prefer the
organization of a computerized write-up. Bilingual or ELL students should have no difficulty as they
not only have peer instruction, but all concepts used in the lab have been previously addressed and
students are constructing new knowledge together. Since the teacher is not introducing new terms
or ideas, there is no risk of misunderstanding.
11.
Homework:
1) What difficulties did you have in the engineering and design process ? (List at least one)
How did you overcome these difficulties?
2) What was your contribution to the design process?
3) List 3 engineers (aside from aerospace and mechanical) that you think would be
involved in space travel? For each one, list specifically what their job would be and why
it is important.
4) If we assume that the Probe is at least 6 mi. above the surface of the moon:
a. What is the force being exerted on the piece of rocket that is plummeting to the
surface by the moon.
b. As a result of this, what would the acceleration be?
c. If the piece of rocket were falling to earth under the same conditions (from 6 mi.
up)
i. what would be its final velocity as it crashes to earth?
ii. How does this compare to the velocity as it hits the moon?
iii. What assumptions are you making in this calculation?