Completed Rubric for the Controlled Experiment
Exit Project Titled “Balloon Powered Car Experiment”
A. Title
Title: “Balloon Powered Car Experiment”
Score: 1 – “The title is present but does NOT correctly state the independent variable or the
dependent variable.”
Comments: The title is present, but it does not state the independent variable (mass of car) or the
dependent variable (distance traveled.) A title that would have received total credit is, “The effect of
mass on the distance a balloon-powered car travels.”
B. Question
Question: “How will weight affect how far a balloon powered car goes?/ How far will a balloonpowered car go carrying differing amounts of weight?”
Score: 3 – “The question states the independent variable and the dependent variable, and is
testable.”
Comments: The question, though stated slightly differently on the project board twice, includes
both IV, DV and is testable. Using the term mass instead of weight would have made these
questions stronger.
C. Hypothesis
Hypothesis: “If more weight is added to the balloon-powered car, then it will travel a shorter
distance because the more mass an object has, the more force it takes to move it.”
Score: 3 – “The hypothesis predicts the effect that changing the independent variable will have on
the dependent variable, and explains the reason for the prediction using scientific reasoning
(‘because…’) that is supported by cited background research.”
Comments: The hypothesis clearly predicts the effect that changing the IV will have on the DV.
The “because” is present, but is not supported completely by the background research found in the
introduction. Including Newton’s Second Law of Motion and using mass instead of weight would
have made the “because” stronger. Points were taken off for this in background research (section
D).
D. Background research
Score: 2 – “Background Research is relevant to the topic and is found to support either the
‘..because…’ portion of the hypothesis, or the “scientific reasoning” portion of the Discussion”
Comments: The background research in the introduction is fairly relevant, including explanations
of Newton’s Third Law of motion, momentum and friction. Including Newton’s Second Law of
Motion and using mass instead of weight would have made the background research stronger and
the student would have received a “3” for this section.
E. Investigation Design (ID)
Score: 3 – “All 5 components of the investigation’s design (or ID) are stated correctly and
explicitly, AND only one independent variable (or IV) is allowed to change at a time, AND there are
multiple trials”
Comments: The IV, DV, Levels of IV, # of trials and Constants are correctly mentioned throughout
the poster board in the procedure, a section titled, “Variables,” and a table presenting results. More
constants could have been included such as the car, surface, balloon.
F. Procedure
Score: 2 – “Materials are listed, and a step by step procedure is described, but some steps are
missing or incomplete or not consistent with the ID.”
Comments: A step-by-step procedure, including materials is present along with a diagram and
photograph of the balloon powered car. There was a small inconstancy in materials used to add
mass to the car. In the discussion, it is stated that at one point, 25 grams of clay was added to the
car, not a 25-gram mass as noted in the materials list. If more detail for the construction of the
balloon-powered car were included as well as a little more detail in the procedure the student would
have received a “3” for this section.
G. Data/Results
Score: 3 – “Data table(s) and graph(s) are accurate, include labels (titles, correct units of
measure), and are relevant to the original question. Trends or patterns in the data are identified
and summarized. Data address the hypothesis and the correct tables and/or graphs have been
chosen to clearly answer the original question.”
Comments: The data table and bar graph are accurate, include correct labels and are relevant to the
original question. The averages are missing on the data table, but it is included in the graph. Trends
and patterns are identified and summarized in the observation section. A line graph or scatter-plot
with a trend line with appropriate spacing along the X-axis might have resulted in more accurate
representations of the data
H. Discussion/Conclusion
Score: 3 – “Discussion/Conclusion makes a claim (i.e., the hypothesis is or is not supported…),
supports the claim with evidence, and uses reasoning--in the form of connections to scientific
concepts--to relate claim and evidence. It is important that the Discussion/Conclusion refer to
relevant scientific concepts (content knowledge) to explain why the claim and evidence are related.
Scientific sources supporting results should be referred to and cited in the discussion. Reflections
and ‘Next Steps’ are included in the Discussion/Conclusion.”
Comments: Claim based on the hypothesis is supported with evidence from this investigation and
scientific reasoning present in the introduction. Reference to Newton’s Second Law is still missing,
but the term “weight” is replaced with the more accurate term “mass”. Includes reflections, next
steps and sources of possible experimental error.
I. Literature Cited
Score: 0 – “Not attempted.”
Comments: No sources were cited even though there is background research present in the
introduction.
Final Score- 42/51 or 82%
Project Section
A. Title
B. Question
C. Hypothesis
D. Background Research
E. Investigation Design (ID)
F. Procedure
G. Data/Results
H. Discussion/Conclusion
I. Literature Cited
Score (0-3)
Weight
x1
x1
x2
x2
x2
x2
x3
x3
x1
Total weighted score
Final Score (%) = Total weighted score/51 x 100
1
3
3
2
3
2
3
3
0
Weighted Score
= 1
= 3
= 6
= 4
= 6
= 4
= 9
= 9
= 0
= 42 (51 max)
= 82%