EXPER MENTAL
DES GN
North Carolina Science Olympiad
Coaches Institute
October 12-13, 2007
Michael D. Huberty
Minnesota Science Olympiad President Mounds View High School
Arden Hills, Minnesota
michael.huberty@moundsviewschools.org
Pages 2-17 of this handout are modified from “An Experiment Workbook for Students 2004-2005”
by Colleen Bizzell and Brian Bizzell and used by permission from the authors
ACTUALLY DOING THE EXPERIMENT: HINTS FOR COMPETITION
CHOOSING AN EXPERIMENT
Choosing your experiment doesn’t sound like it should be hard, but get three heads together and a lot of
stress and suddenly it isn’t so easy. The most important thing to remember is there aren’t any points awarded for
creativity. You don’t have to do the best possible experiment, just one that fits the topic area. Any topical
experiment that gives you graphable, analyzable data will work. Take the first thing that pops into your head and
run with it. You should be writing your statement of problem and hypothesis within minutes of starting the
competition.
TIME CONSIDERATIONS
There is never enough time. Don’t complain about it, just learn to work with the time you do have. Pay
attention to how many points each rubric area is worth and don’t spend too much time on the small point things.
Break things up between you and your partners. You should work together to come up with the experiment you
are going to do. However, once you decide, split the work among you.
WORKING WITH YOUR PARTNERS
Working with partners can be one of the most difficult parts of this event. However, it is also the most
valuable. No one is alone anymore; we all have to learn to work with other people. The most important thing is
to trust your partners. Work together before the competition. Have a plan on how you are going to split the work
when you get to competition, and follow it. Give everyone a job and trust that they will do their job well. Say,
for example, you spit things so that one person writes the beginning parts while the other two actually conduct the
experiment. If you are one of the experimenters, you need to trust that your writer knows what they are doing.
Don’t read over their shoulder or correct them unless they ask for help. You have your own job to do.
SOME PRACTICE SUGGESTIONS
The key to this event is practice. Since time is limiting, you won’t have a chance to “figure it out” when
you get to the competition. You need to know exactly what to do before you get there.
When you start, don’t worry about time. Worry about completing your report. It is better to practice
writing a good report than to practice writing a hurried one. Speed will come with practice.
Think about the type of equipment you will see in competition. It’s hard to get 10-25, even 50 copies of
sophisticated equipment. Much of the time you will have little more than a pile of junk and maybe a balance or
hot plate. Practice with similar equipment. Also, don’t complain about the equipment. Ancient scientists learned
even more with even simpler equipment.
Take the same pile of junk and come up with as many experiments as you can with it. Practice coming up
with experiments quickly.
Practice all kinds of experiments. Just because physics experiments are easiest doesn’t mean you won’t get
a biology or chemistry topic. The more topics you are prepared for, the easier it will be the day of the
competition.
THE DAY OF THE COMPETITION
Remember to bring safety goggles, at least one writing instrument per person, a timepiece, ruler, and a nonprogrammable calculator. It’s hard to write a good experiment if you forget your equipment.
Watch your terminology. This isn’t a vocabulary contest. If you don’t know the right word, use one you
do know.
Don’t rely on the abbreviated rubric given to you in competition. Sometimes it can be VERY
abbreviated. You should know the rubric backwards and forwards before you ever get to the competition. If the
rubric says variables, you should know this means to include the independent, dependent, and controlled
variables.
Be sure to save plenty of time for your analysis of data and conclusion.
Make sure you write legibly with decent grammar and spelling. If the even supervisor can’t read or
understand what you’ve written, you aren’t going to get points for it.
2
RUBRIC AREA SUMMARY
Experiment: a process in which some treatment is applied to a number of subjects and its effects
observed
STATEMENT OF PROBLEM
Non-yes/no question that defines the topic of the experiment
It is NOT the same as the topic area or assigned problem
It defines the specific relationship you wish to study
It can be a statement or question, but not a yes/no question
It must be clearly testable with the materials provided
HYPOTHESIS
A statement predicting the relationship between the independent and dependent variables that
can be tested
The hypothesis must predict a relationship or trend
It must take a stand
It needs to includes the independent and dependent variables
If (the independent variable) (increases/decreases) then (the dependent variable)
will (increase/decrease/remain the same)
A brief rationale should be included
VARIABLES
Factors that can change in an experiment
Independent variable: the manipulated variable
A variable that is purposely changed or manipulated
The IV should be operationally defined (units!)
Operationally defined: clearly stating how a variable will be measured or described
You should test 3-5 levels of the IV
Levels of the independent variable: the values of the independent variable that one tests
Dependent Variable: the responding variable
The variable that changes in response to the changes in the independent variable
The DV should be operationally defined
Constants (Controlled variables)
Factors that don’t change in the experiment: factors with a fixed value
These can be other possible independent variables that you are choosing to hold constant
At least 4 should be listed
EXPERIMENTAL CONTROL: the standard of comparison (SOC)
A trial used to detect and measure hidden variables
The control can be a zero treatment, a level of IV, or an outside control
The control is often specific to the goal of your experiment
You should include a rationale for why you choose the control you did
MATERIALS AND PROCEDURE
Materials
A listing of all the equipment used in an experiment
The materials should be listed separately from the procedure
3
It should include everything you use, but not any extra materials
You should include model numbers and brands where appropriate
Procedure
A listing of exactly how one did an experiment
It should contain enough information so another could repeat the experiment
You only need to write for one level of IV, then say repeat steps ____
You should have repeated trials at each level of the IV
Diagrams are extremely helpful
Qualitative data: data based on a non-standard scale
Quantitative data: data based on measurement
QUALITATIVE OBSERVATIONS
The stuff you notice during the course of the experiment
They should include a qualitative representation (description) of the data
You should include procedural irregularities
Also include any extra information that you notice but doesn’t directly relate to the DV
You should include observations throughout course of experiment
QUANTITATIVE RESULTS
Data Table
A chart that displays the data collected in an experiment
Make sure the table is organized
The table should have a title
All columns and rows should be labeled including units
Use correct significant figures
Significant figures: the number of digits in a number that have meaning
Include ALL raw data
Include a summary table of important data
Calculated values should be in their own columns
Graphs
A pictorial representation of the data
Be sure to use an appropriate type of graph, generally a bar or line graph
Any trends in data should be represented
Graphs should have titles
All axes should be labeled including units
Use an appropriate scale
Include a figure legend to briefly explain the graph
Statistics
Include a measure of central tendency (mean, median, mode)
Measure of central tendency: value at the center or middle of a data set
Mean (average): found by adding all the values obtained and dividing by the total
number of values
Median: the middle value when all the values are arranged in order of increasing or
decreasing magnitude
Mode: the value that occurs most often
Include any other appropriate statistics
Measure of variation (range, standard deviation, frequency table, histograph)
Range: the difference between the highest value and the lowest value
Standard deviation: a measure of how closely individual data points are arranged around
the mean
4
Frequency table: measure of variation for qualitative data; lists the categories in one
column and the number of times each occurred in another
Histograph: a pictorial representation of a frequency table
Regression line – Line of best fit showing the trend of the data
Percent error
Percent error: measure of how close an experimental value is to the expected value
ANALYSIS OF RESULTS
An explanation of the data obtained including any trends found and relevant statistics
Include a discussion of what the data means
Discuss trends and what they mean
Include statistics and what they mean
Discuss unusual data points, include why they may have occurred and whether they are
statistically significant
Do not just restate the data, discuss it.
It’s ok to throw out ideas that you aren’t sure of.
POSSIBLE EXPERIMENTAL ERRORS
A statement indicating any sources of error in an experiment
Random Error: error introduced because of limited precision of instruments. It can be either higher or
lower than correct value
Mess-up Error: error introduced into an experiment because of a known mistake done by the
experimenter or because of a faulty/poor procedure
Systematic Error: error introduced because of faulty equipment. It is normally only higher or lower than
correct value
This is a separate section from analysis of results.
You should discuss important information about data collection
Give possible reasons for errors
Discuss the possible effects of errors on the data
CONCLUSION
A statement describing the purpose, major findings, and explanation of findings of an experiment
A one paragraph summary of your experiment
You should include the purpose of doing the experiment
You should restate your hypothesis
You should evaluate your hypothesis according to the data
Does the data support your hypothesis?
Give reasons to accept or reject your hypothesis
Don’t include lots of numbers in your conclusion
RECOMMENDATIONS FOR FURTHER EXPERIMENTATION AND PRACTICAL APPLICATIONS
Give at least one suggestion to improve the particular experiment you did
(Other than we need better equipment or more time)
List another possible experiment to examine your same hypothesis
Give at least one suggestion for a future related experiment
Give at least one practical application for the specific experiment done
Remember this section is only worth 4 points so don’t go overboard
5
Experimental Design
2!!2 MN State Science Olympiad
Colleen Bizzell, Supervisor
T ASK : P ARACHUTES
You must conduct an experiment dealing with any aspect of the topic area of parachutes. (Hint: You should do an experiment that
gives you numerical data.) You must use at least two of the materials below. You have 50 minutes to conduct, write up and
CLEAN up your experiment. Good Luck!
Your materials:
AT YOUR TABLE:
(12) MARBLES
(10) HEX NUTS
(1) PLASTIC SHOPPING BAG
(5) POPSICLE STICKS
(2) PAPER NAPKINS
(2) NEWSPAPERS
(1) SMALL PLASTIC CUP
(1) WHITE GARBAGE BAG
AT DISTRIBUTION CENTER:
(_ ) BLACK PLASTIC GARBAGE BAG
FISHING LINE (2LB AND 6LB)
RUBBERBANDS (ASSORTED SIZES)
MASKING TAPE
SCISSORS
(1) LARGE PLASTIC CUP
IF YOU BROUGHT THEM:
STRING
3”x5” CARDS
PAPER TOWELS
RULER
TIMER
You may also use as much lined and graph paper as you need to write your report (but only to write the report).
Your write-up must include all of the following parts clearly labeled! (Rubric points are given in parentheses):
1. Statement of Problem (4)
2. Hypothesis with rationale (4)
3. Variables (10)
Dependent, Independent, Controlled
4. Standard of Comparison (3)
5. Materials and Procedure (8)
6. Qualitative Observations (4)
7. Quantitative Data: including data tables, graphs, and statistics (16)
8. Analysis and Interpretation of Data (10)
9. Possible Experimental Errors (3)
10. Conclusion (4)
11. Recommendation for Further Experimentation (4)
Clean-up:
1. Please discard any materials which you have folded, torn, cut, taped, or in any
other way permanently modified. Place all unused items back on your table. Get
replacement materials for the items you threw away from the front of the room.
2. Staple and turn in your write-up at the front of the room. Make sure your
school name and number are on it!!!,
3. You may take this page with you when you finish.
YOU MUST BE COMPLETELY FINISHED WITH YOUR WRITE-UP AND CLEAN-UP PROCEEDURES 50
MINUTES AFTER THE START OF THE ROUND. THIS TIME LIMIT WILL BE STRICTLY ENFORCED!!!
6
SAMPLE EXPERIMENTAL DESIGN WRITE-UP (FROM A SIMILAR PARACHUTE TASK)
The effect of parachute area on the time of descent of a mass
Statement of Problem: How does the area of a parachute effect the time of descent of an object?
Hypothesis: If the area of a parachute increases, then the time of descent for the mass will
increase.
Independent Variable: Area of a parachute in cm2 (36, 64, 100)
Dependent Variable: Time of descent in seconds
Controlled Variables:
1. The parachutes were made out of the same material.
2. All parachutes were attached to the mass in the same way as described in the
procedure.
3. The same mass was used for all trials (20g).
4. The parachutes were dropped from the same height (the ceiling ~8ft)
5. The parachutes were all the same style and shape, just different sizes.
Standard of Comparison: The mass without a parachute. This will tell us how long it take the
mass itself to fall the distance. This will allow us to determine the effect of the parachute.
Materials:
1 plastic trash bag
Stopwatch
Ruler
String
Tape
Scissors
1 mass (20g)
Procedure
1. Cut three square parachutes out of the trash bag:
one 6cm on a side, one 8cm, and one 10cm.
2. Cut 4 6cm pieces of string for each parachute
3. Tape one end of each piece of string to the four corners of the parachute.
4. Tape the other ends to the mass
5. Grab the parachute by the center and drop from the ceiling
6. Determine the amount of time it takes for the mass to hit the floor.
7. Repeat step 5-6 two more times
8. Repeat steps 4-6 for each of the parachutes
9. Also drop and time just the mass from the same height
Hold here
parachute
Qualitative Observations
string
The smaller the parachute the faster the mass fell
It was hard to time the smallest parachute and the mass without a parachute
7
mass
The string broke off the mass on the second trial of the 8cm parachute and had to be retaped.
Sometime the parachute didn’t open as well as others. If the parachute didn’t open at all,
we repeated that trial.
Data Tables
Table 1: The effect of parachute area on the time of descent of a mass
Parachute
Time of descent (s)
Area (cm2)
Trial 1
Trial 2
Trial 3
0
0.15
0.12
0.10
36
0.19
0.20
0.18
64
0.33
0.35
0.33
100
0.49
0.51
0.54
Table 2: Most important data
Parachute Area (cm2) Average Time of decent (s)
0
0.12
36
0.19
64
0.34
100
0.51
Sample Calculations
Area = length of side 1 * length of side 2
Area = 6*6=36
Average =(T1+T2+T3)/3
Average =(0.15+0.12+0.10)/3=0.12
Graph
The Effect of Parachute Area on Time of
Descent
Time of Descent (s)
0.6
0.5
The graph shows that as the area of the
parachute increases, the time of descent
increases. Error bars are shown as one
standard deviation.
0.4
0.3
0.2
0.1
0
0
y = 0.004x + 0.0897
R2 = 0.9636
50
100
150
Parachute Area (cm2)
8
Statistics
Parachute Area
(cm2)
0
36
64
100
Time of Descent (s)
Average SD
Range
0.12
0.03
0.05
0.19
0.01
0.02
0.34
0.01
0.02
0.51
0.03
0.05
Analysis of Results
The data indicate a linear trend between the area of a parachute and the time of descent of
a mass. This means that as the area of a parachute increases, the time of descent of a mass also
increases. The R2 value was 0.96 which indicates that 96% of the data points can be described
by this regression line. The average time of descent of the 36cm2 was a little faster than the
regression line would indicate. The standard deviation of this point is no larger than any other
point, thus this “extra speed” is not due to a large variation in the data. However this point is not
very far off, and is probably within the acceptable range of error of the experiment.
Possible Experimental Error
The string breaking off the mass on the 64cm2 parachute did not seem to effect the data.
The greatest error in this experiment was the timing of the small parachutes. These parachutes
fell very fast and it was difficult to accurately time them. This error could cause the value to be
either higher or lower than the real value.
Conclusion
The purpose of our experiment was to determine the effect of the area of a parachute on
the time of descent of a mass. The data supported our hypothesis that as the area of a parachute
increased, the time of descent of a mass would increase. The data showed a linear relationship
between area and time of descent.
Recommendations for further experimentation and practical applications
This particular experiment can be improved by testing more parachute areas. Another
way to look at our hypothesis is to make parachutes out of a different material, such as cloth, and
see if the same relationship holds. A related experiment would be to look at how the size of a
mass effects the time of descent. A practical application of this experiment would be sky diving.
It could be used to determine the optimum parachute size.
9
Directions: Fill in the missing parts of this experiment
Effect of ancymidol concentration on the percent germination of Arabidopsis seeds
Statement of Problem: What is the effect of ancymidol (a plant growth inhibitor) concentration
on the percent germination of Arabidopsis seeds?
Hypothesis:
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Independent Variable:
______________________________________________________________________________
Dependent Variable:
______________________________________________________________________________
Controlled Variables:
1. Plants were grown under the same lighting conditions
2. Plants were grown at the same temperature
3. The same seed lot was used for all trials (seeds same type and same age)
4. The same batch of MS-agar media was used to make each ancymidol concentration
5. The same stock of ancymidol (ancy.) was used
Experimental Control:
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Materials:
32mM ancymidol (Sigma)
24 petri plates
6 L MS media + agar
1000 Arabidopsis seeds
Florescent light / growth chamber
Refrigerator (Kenmore 18)
Procedure:
1. The MS media + agar was heated to boiling and allowed to cool until it was 65oC.
2. The amount of ancymidol given in Table 1 was added to 1L of MS media + agar and
mixed well to make each concentration of ancymidol.
3. The mix of ancymidol and MS + agar was poured into plates. 50 ml each plate. Fig 1
4. The plates were allowed to cool and solidify.
5. Approximately 75-150 Arabidopsis seeds were placed (equally spaced) on the plates
Fig 2
10
5. The plates were placed in the fridge for 2 days.
6. The plates were placed under florescent lighting for 9 days.
7. The number of germinated plants and non-germinated seeds were counted on each
plate.
Figure 1: Making petri plates
Table 1: Amt ancy used to make plates
Concentration ul 32 mM Ancy
of Ancy (uM) added to 1L MS
0
0
2
62.5
4
125
8
250
16
500
32
1000
Ancy
MS Media
+ agar
petri plates
Figure 2: Seeds on petri plates
. . . .
. . . . . .
. . . . .
. . . .
Arabidopsis
seed
Seeds equally spaced
Qualitative Observations
Not all the seeds were spaced equally on the plates
Some plates got more seeds than others
A few of the plates froze in the fridge.
When the plates thawed they were cracked and had water on them
The plates that didn’t freeze, didn’t have standing water on them
The plants on the plates without ancy were larger than those on the plates with ancy
The plants on the plates with ancy were darker green than without ancy.
Ancy
Conc.
0uM
2uM
4uM
8uM
16uM
32uM
Data Table
Table 1: Effect of Ancymidol concentration on the Percent germination of Arabidopsis
Trial 1
Trial 2
Trial 3
Trial 4
ger Non Tot %
ger Non Tot %
ger Non Tot %
ger Non
87 0
87
100 82
0
82
100 114 0
114 100 101 1
87 2
89
97.8 95
2
97
97.9 86
7
93
92.4 82 25
60 49
109 55.0 62
39
101 61.3 57
46
103 55.3 45 67
2
216 218 0.9
1
163 164 0.6
2
83
85
2.3
1
99
0
132 132 0.0
0
135 135 0.0
0
94
94
0.0
0
100
9
168 168 0.0
0
167 167 0.0
0
74
74
0.0
0
154
ger = germinated
Non = non germinating
tot = total seeds planted
Sample Calculations
% = germinating/total
%=87/89 = 97.8
11
Tot
102
107
112
100
100
154
%
99.0
76.6
40.2
1.0
0
0
Table 2: Most important Data
Graph
Statistics
Analysis of Results
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
12
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Possible Experimental Errors
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Conclusion
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Recommendations for further experimentation and practical applications
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
13
Effect of ancymidol concentration on the percent germination of Arabidopsis seeds
Statement of Problem: What is the effect of ancymidol (a plant growth inhibitor) concentration on
the percent germination of Arabidopsis seeds?
Hypothesis: If the concentration of ancymidol increases then the percent germination of
Arabidopsis seeds will decrease. Ancymidol is a plant growth inhibitor, thus it will reduce the
likelihood of seeds germinating.
Independent Variable: Concentration of Ancymidol in uM (0, 2, 4, 6, 16, 32)
Dependent Variable: Germination of Arabidopsis seeds as a percent
Controlled Variables:
1. Plants were grown under the same lighting conditions
2. Plants were grown at the same temperature
3. The same seed lot was used for all trials (seeds same type and same age)
4. The same batch of MS-agar media was used to make each ancymidol concentration
5. The same stock of ancymidol (ancy.) was used
Experimental Control: The trial without any ancymidol. This will tell us the percent germination
of the seeds themselves in the particular conditions that we are using to grow the seeds. If all the
seeds do not germinate without ancymidol then we should not expect them all to germinate with any
concentration of ancymidol. This control will allow us to see the effect of the ancymidol separate
from the other conditions we are growing the seeds in.
Materials:
32mM ancymidol (Sigma)
24 petri plates
6 L MS media + agar
1000 Arabidopsis seeds
Florescent light / growth chamber
Refrigerator (Kenmore 18)
Procedure:
1. The MS media + agar was heated to boiling and allowed to cool until it was 65oC.
2. The amount of ancymidol given in Table 1 was added to 1L of MS media + agar and
mixed well to make each concentration of ancymidol.
3. The mix of ancymidol and MS + agar was poured into plates. 50 ml each plate. Fig 1
4. The plates were allowed to cool and solidify.
5. Approximately 75-150 Arabidopsis seeds were placed (equally spaced) on the plates
Fig 2
5. The plates were placed in the fridge for 2 days.
6. The plates were placed under florescent lighting for 9 days.
7. The number of germinated plants and non-germinated seeds were counted on each
plate.
14
Figure 1: Making petri plates
Table 1: Amt ancy used to make plates
Concentration ul 32 mM Ancy
of Ancy (uM) added to 1L MS
0
0
2
62.5
4
125
8
250
16
500
32
1000
Ancy
MS Media
+ agar
petri plates
Figure 2: Seeds on petri plates
. . . .
. . . . . .
. . . . .
. . . .
Arabidopsis
seed
Qualitative Observations
Not all the seeds were spaced equally on the plates
Seeds equally spaced
Some plates got more seeds than others
A few of the plates froze in the fridge.
The 2 and 4uM plates of trial 4 froze.
When the plates thawed they were cracked and had water on them
The plates that didn’t freeze, didn’t have standing water on them
The plants on the plates without ancy were larger than those on the plates with ancy
The plants on the plates with ancy were darker green than without ancy.
Data
Ancy
Conc.
0uM
2uM
4uM
8uM
16uM
32uM
Table 1: Effect of Ancymidol concentration on the Percent germination of Arabidopsis
Trial 1
Trial 2
Trial 3
Trial 4
ger Non Tot %
ger Non Tot %
ger Non Tot %
ger Non
87 0
87
100 82
0
82
100 114 0
114 100 101 1
87 2
89
97.8 95
2
97
97.9 86
7
93
92.4 82 25
60 49
109 55.0 62
39
101 61.3 57
46
103 55.3 45 67
2
216 218 0.9
1
163 164 0.6
2
83
85
2.3
1
99
0
132 132 0.0
0
135 135 0.0
0
94
94
0.0
0
100
9
168 168 0.0
0
167 167 0.0
0
74
74
0.0
0
154
ger = germinated
Non = non germinating
tot = total seeds planted
Sample Calculations
% = germinating/total
%=87/89 = 97.8
15
Tot
102
107
112
100
100
154
%
99.0
76.6
40.2
1.0
0
0
Table 2: Most important Data: Ancy conc vs % germination
Ancy.
% Germination
Conc. (uM) Trial 1 Trial 2 Trial 3 Trial 4 Average
0
100
100
100
99.0
99.8
2
97.8
97.9
92.4
76.6
91.2
4
55.0
61.3
55.3
40.2
53.0
8
0.9
0.6
2.3
1.0
1.2
16
0.0
0.0
0.0
0.0
0.0
32
0.0
0.0
0.0
0.0
0.0
Graph
Effect of Ancy Conc on Germination Rate
Range
1.0
21.3
15.1
1.7
0.0
0.0
Percent Germination
Table 3: Relevant statistics
Ancy.
% Germination
Conc. (uM) Average SD
0
99.8
0.5
2
91.2
10.1
4
53.0
9.0
8
1.2
0.8
16
0.0
0.0
32
0.0
0.0
120
y = -12.977x + 106.72
R2 = 0.9731
100
80
60
40
20
0
0
10
20
30
40
Ancy Conc (uM)
Analysis of Results
For the concentrations of ancymidol that still allow the seeds to germinate we found a linear
relationship between ancymidol concentration and percent germination. This means that more
seeds germinated at lower concentrations of ancymidol. Above 8uM Ancymidol, however, no
germination occurred. Almost all the seeds germinated in the control indicating that the reduced
germination was caused by the ancymidol. The linear portion of the data fit the best-fit line fairly
well. R2 is 0.97 indicating that the equation describes 97% of the data points. All but the 2uM data
point fall on the best-fit line within one standard deviation. The 2uM point is a little high. However
trial 4 of the 2uM is low. This plate froze in the refrigerator possibly reducing the germination rate
on this plate. If this plate had not frozen there would likely have an even higher germination rate
which would cause the average to increase, not decrease. It is possible that this data point is a clue
that the relationship between ancy concentration and percent germination is not linear, but rather the
germination rate may slowly decrease until a certain ancy concentration and then drop rapidly.
More ancy concentrations will have to be examined before this can be determined.
Possible Experimental Errors
Error was introduced when the plates froze in the fridge. These plates had lower than
average germination rates, which in turn lowered the average and increased the range. Without this
error the average germination on 2uM and 4uM ancy would have been higher, though this would
not significantly alter the trends seen in the data.
16
Conclusion
The purpose of this experiment was to determine the effect of ancymidol concentration on
the germination rate of Arabidopsis seeds. The data supported our hypothesis that as the
concentration of ancymidol increases the percent germination will decrease. The data showed a
linear relationship between ancy concentration and percentage germination.
Recommendations for further experimentation and practical applications
This particular experiment can be improved by testing more concentrations of ancymidol
within the linear range. Another way to examine our hypothesis is to grow the plants with
ancymidol in different conditions, such as short days or low light conditions, and see if the
ancymidol still has the same effect. A related experiment would be to look at the effect of fertilizer
amounts on the germination of Arabidopsis seeds. A practical application of this experiment would
be in reducing the germination of plants in areas where they are not wanted such as a sidewalk.
17
EXPERIMENTAL DESIGN
MINNESOTA STATE 2007
Team Number
School Name
Total Points
by Michael D. Huberty
You must design, conduct, and report the findings of an experiment dealing
with the chemical reaction mixing baking soda and vinegar. You have 50
minutes to conduct, write up, and CLEAN up your experiment. Good Luck!
Materials you may use provided at
distribution centers:
1 overflow can
1 graduated cylinder
1 large plastic container
2 plastic test tubes with caps
balloons (you may use up to 10)
baking soda
vinegar
water
rags for cleaning up
Materials you may use if you brought
them:
writing instrument(s)
non-programmable calculator
timepiece
ruler
You may also use as much graph paper as
you need to write your report.
Your write up needs to include all of
the following topics. Rubric points are
given in parentheses. Make sure each
section is CLEARLY labeled.
Statement of Problem (2)
Hypothesis (4)
Variables:
Constants (4)
Independent (3)
Dependent (3)
Experimental Control (2)
Materials (3)
Procedure (6)
Qualitative Observations During
Expt. & Summary of Results (4)
Data Table (6)
Graph(s) (6)
Statistics (4)
Analysis of Results (4)
Possible Experimental Errors (3)
Conclusion (4)
Recommendations for Further
Experimentation & Applications (4)
Clean-up:
1. Clean up any spilled substances. Be sure to wash
all materials that got dirty. Used balloons can be
thrown away. Place all cleaned and unused items
back at the distribution center you got them.
2. Staple your write-up with this page on top. Make
sure your team name and team number is on each
page!!!, Hand in to the event coordinator.
YOU MUST BE COMPLETELY FINISHED WITH YOUR
WRITE-UP AND CLEAN-UP PROCEEDURES 50 MINUTES
AFTER THE START OF THE ROUND.
THIS TIME LIMIT WILL BE STRICTLY ENFORCED!!!
Goggles must be worn at
all times. Failure to comply
with this will result in one
friendly warning. If your
team is given a second
warning about wearing
goggles, your team’s
results will be ranked after
all other teams. If your
team is caught a third time
not wearing goggles, you
will be immediately
disqualified from the event.
EXPERIMENTAL
DESIGN
MINNESOTA STATE 2005
Team Number
School Name
Total Points
Gummy Bears In Space
by Michael D. Huberty, Minnesota Science Olympiad State Director
adapted from an experiment by Richard L. Scheaffer, Mrudulla Gnanadesikan, Ann Watkins, and Jeffrey A. Witmer
You must design, conduct, and report the findings of an experiment dealing with building a device to
launch a gummy bear and measure horizontal distance traveled. You have 50 minutes to conduct,
write up, and CLEAN up your experiment. Good Luck!
Materials provided in plastic bag:
5 popsicle sticks
5 rubber bands
5 gummy bears
2 tape measures (150 cm)
Other materials you may use if you brought them:
writing instruments (hint: makes good fulcrum)
non-programmable calculator
timepiece
ruler
You may also use as much graph paper as you need to write your report.
You write up needs to include all of the following topics. Rubric points are given in
parentheses. Make surre each section is CLEARLY labeled.
Statement of Problem [2]
Goggles must be worn at
Hypothesis [4]
all times. Failure to
Variables: Independent [3], Dependent [3], Constants [4] comply with this will
Experimental Control [3]
result in one friendly
warning. If your team is
Materials and Procedure [8]
given a second warning
Qualitative Observations [4]
about wearing goggles,
Data Table [6]
your team’s results will
Graph(s) [6]
be ranked after all
other teams. If your
Statistics [4]
team is caught a third
Analysis of Results [6]
time not wearing
Possible Experimental Errors [3]
goggles, you will be
Conclusion [4]
immediately disqualified
Recommendation for Further Experimentation [4]
from the event.
Clean-up:
1. Please discard any materials which you have broken, gotten dirty and sticky, or in any other way
permanently modified. Place all unused items back in the plastic bag and give to the event
coordinator. (You may eat gummy bears at your own risk.)
2. Staple your write-up with this page on top. Make sure your team number is on each page!!!,
Hand in to the event coordinator.
YOU MUST BE COMPLETELY FINISHED WITH YOUR WRITE-UP AND CLEAN-UP PROCEEDURES 50
MINUTES AFTER THE START OF THE ROUND.
THIS TIME LIMIT WILL BE STRICTLY ENFORCED!!!
EXPERIMENTAL
DESIGN
SCORING RUBRIC 2005
1.
2.
3.
4.
5.
6.
Statement of Problem: Experimental Question*
* Yes/No questions not valid.
_____ Statement narrows down topic area
(implies a specific experiment),
generalized variables included
_____ Problem is clearly testable
Hypothesis
_____ Statement predicts a relationship or trend
_____ Statement gives specific direction to the
predictions(s): A stand is taken.
_____ Prediction includes both independent and
dependent variables
_____ A rationale is given for the hypothesis based
on prior knowledge
Variables
Independent Variable: Factor being manipulated
_____ Ind var correctly identified
_____ Ind var operationally defined (include units)
_____ At least three levels of ind var are given to
be tested
Dependent Variable: Factor which responds
_____ Dep var correctly identified
_____ (2) Dep var operationally defined (include units)
Constants (Controlled Variables): Factors held constant
_____ One constant correctly identified
_____ Two constants correctly identified
_____ Three constants correctly identified
_____ Four constants correctly identified
Experimental Control (Standard of Comparison)
_____ A standard of comparison is identified
_____ The standard of comparison makes logical
sense for the experiment being done
_____ A rationale is given for why the standard of
comparison was choosen
Materials and Procedure
_____ All materials used are listed properly (no extras)
_____ Materials listed separately from procedure
_____ Procedure well organized
_____ Procedure is in a logical sequence
_____ (2) Enough information is given so another
could repeat procedure
_____ Diagram(s) used and clear
_____ Repeated trials
Qualitative Observations
_____ Qualitative summary of data/results given
_____ Observations about procedural irregularities
_____ Observations about results not directly
relating to dependent variable (extra info)
_____ Observations given throughout course of
experiment
7.
8.
9.
10.
11.
12.
13.
Team Number
School Name
Total Points
Data Table
_____ ALL raw data is given
_____ ALL data has units
_____ ALL data reported using correct significant
figures
_____ Summary column or condensed table with
most important data included
_____ Table(s) labeled properly (titles)
_____ Example calculations are given
Graph(s)
_____ Appropriate type of graph(s) used
_____ Graph(s) titled
_____ Axes labeled properly
_____ Units included in graph(s)
_____ Trends in data are represented
_____ Appropriate scales used on axes
Statistics
_____ Measure of central tendency (e.g. mean, median)
_____ Measure of variation (e.g. range, stand deviation)
_____ Regression analysis (e.g. line of best fit)
_____ Other appropriate statistic used (e.g. % error)
Analysis of Results*
*All statements must be supported by the data
_____ All data discussed and interpreted
_____ Discussed unusual data points, why they
may have occurred, and whether they are
significant
_____ Discussed trends in data and what they mean
_____ Discussed what the statistics mean
_____ Enough detail is given to understand data
_____ Response is clear and concise
Possible Experimental Errors
_____ Possible reasons for errors are given
_____ Important info about data collection given
_____ Effect errors had on data discussed
Conclusion
_____ Hypothesis is evaluated according to data
_____ Hypothesis is re-stated
_____ Reasons to accept/reject hypothesis given
_____ All statements are supported by the data
Recommendations for Further Experimentation
_____ Suggestions for improvement of specific
experiment are given (other than “need
more time, better materials’)
_____ Suggestions for other ways to look at
hypothesis given
_____ Suggestions for future experiments given
_____ Practical application(s) of experiment giv
Ties are broken by the professional judgment of the event coordinator as to the better report.