AP Lab Report Rubric
Far Below Expectations – 0 points Below Expectations – 2 points Meets or Exceeds Expectations – 4 points
1. Neatness and
Organization
The lab report fails to meet two or more of
the expectations for neatness and
organization.
The lab report fails to meet one of the
expectations for neatness and organization.
1. The lab is legibly written in blue or black pen.
2. The lab sections are in correct order.
3. Pages have not been torn from the lab book.
4. Mistakes are “lined through” rather than
covered with white-out.
5. No more than three spelling/grammatical errors
2. Title and Date The lab report fails to meet both of the
expectations for Title and Date.
The lab report fails to meet one of the two
expectations for Title and Date.
1. Title is present and is descriptive of the lab.
2. Date is recorded and accurate.
3. Purpose Purpose is missing, or is only loosely related
to the lab being performed.
The Purpose addresses the procedural aspects
of the lab, but does not accurately summarize
the theoretical foundation of the experiment.
Purpose accurately describes the theory that is
intended to be reinforced by performing the lab.
4. Procedure Procedure is missing altogether, or missing
important steps.
Procedure is a mostly copied directly from the
lab description, with little attempt at brevity.
Procedure is a brief summary of each of the steps
taken in completing the lab. It is NOT an exhaustive
description containing minute detail.
5. Data The student has recorded data after
completion of the lab, or fails to meet BOTH
expectations 2 and 3 of the Data section.
The lab report fails to meet either expectation 2
or 3 of the Data section.
1. Data is recorded directly into the lab book during
experimentation.
2. Data is neatly organized (in tables if appropriate),
and is easy to interpret.
3. All data is correct with regard to significant
figures and labels.
6. Calculations
and Graphs
The student makes more than 5 errors in
graphing, labeling, calculations, and
significant figures or omits entire graphs or
sets of calculations.
The student makes 3 to 5 errors in graphing,
labeling, calculations, and significant figures.
The student makes no more than 2 errors in
graphing, labeling, calculations, and significant
figures.
7. Conclusions Conclusion is missing, or is in conflict with
the student’s experimental results.
Conclusion is present, and does not conflict
with the student’s experimental findings, but
fails to address the theoretical basis for the lab.
The Conclusion succinctly describes what can be
concluded from the experimental results. It is aligned
with a well-written statement of Purpose at the
beginning of the lab.
8. Discussion of
Theory
Discussion of theory is missing, or does not
adequately address both of the expectations
for this section.
Discussion of theory is present, but fails to
correctly address one of the two expectations of
this section.
1. Addresses the theory demonstrated by the lab
2. Explains how the calculations do/do not support
the theory and fulfill the purpose of the lab
9. Error Analysis The report fails to meet 2 (or all 3) of the
expectations for error analysis.
The report fails to meet 1 of the expectations
for error analysis.
1. Relative error, if appropriate, has been
calculated.
2. Specific sources of experimental error are
addressed.
3. Write-up analyzes the effect of errors on the
magnitude of calculated quantities.
10. Questions Post-lab questions contain more than 3
errors, or some answers have been omitted.
Post-lab questions contain 2 to 3 errors. Post-lab questions contain no more than one error in
total.
Some Lab Write-up Examples
The following table gives examples of laboratory answers for the “Density of Salt Solutions” lab.
Below Expectations – 2 points Meets or Exceeds Expectations – 4 points
Title
“Salt Solution Density Lab” “Determination of the Relationship Between the Density and
Concentration of Sodium Chloride Solutions”
Purpose
“The purpose of the lab is to learn to find the density of salt
solutions.”
The purpose of the lab is to develop a mathematical model relating
the concentration of a solution to its density, and to use this model
to determine the concentration of solutions of unknown
concentration from their densities.”
Procedure
“Measure out 10.00 mL of the 5% NaCl solution using a
pipet and a graduated cylinder, being careful not to lose any
solution. Place the graduated cylinder on an analytical
balance and determine its mass to three decimal places.
Record the mass in the lab book.”
“Using an analytical balance, determine the masses of 10.00 mL
samples of each of the solutions of known concentration.”
Data
5% solution = 10.012 g
10% solution = 10.180 g
15% solution = 10.230
Concentration Mass (g)
5% 10.012
10% 10.180
15% 10.230
Calculations and Graphs
Density = 10.012 g/10.00 mL = 1.0012 g/mL
(significant figures error)
Density = 10.012/10.00 = 1.001 g/mL
(labels not present in calculation)
Density = m/V (fundamental equation shown)
Density = 10.012 g/10.00 mL = 1.001 g/mL
(labels present throughout calculation, significant figures rules
observed)
Conclusions
“We demonstrated that it is possible to measure the
densities of solutions, and to find the concentrations of
unknowns.”
“We demonstrated that a linear relationship exists between the
density and concentration of sodium chloride solutions, and that
the relationship can be used to make predictions about the
properties of solutions of unknown concentration.”
Discussion of Theory
“We showed that as the concentration of a solution
increases, the density of the solution also increases linearly.
Our data supports this conclusion. The purpose of the lab
was fulfilled.”
“As the concentration of a solution increases, the density of the
solution increases in linear fashion. Our data supports this
concept, within reasonable margins of error. The purpose of the
lab was fulfilled when we were able to use the mathematical
model for this linear relationship to predict the concentration of
solutions of unknown concentration based on their densities.”
Error Analysis
“We failed to take into account the mass of the graduated
cylinder when finding the mass of the solutions.”
“We failed to take into account the mass of the graduated cylinder
when finding the mass of the solutions. As a result, the mass of
each solution was too high, and the resulting density was also too
large.”
