Lab Report Rubric (Bachelor's)
Bachelor's · General · 6 criteria · 100 points
This rubric puts half its points on results (25) and discussion (25). Introduction and methods carry 15 each; conclusion and format carry 10 each. Both halves reward precision: figures with axis labels and units, and a discussion that names each source of error and its effect on the data instead of blaming 'human error'.
Criteria and levels
| Criterion | Exemplary | Proficient | Developing | Beginning |
|---|---|---|---|---|
| Introduction and hypothesis15 ptsBackground on the scientific question, the purpose of the experiment, and a testable hypothesis with a prediction. | Exemplary · 15 ptsThe introduction explains the relevant background in a few paragraphs with at least two sources cited in APA 7 format, states the purpose of the experiment, and ends with a clearly worded, testable hypothesis plus a specific prediction (if X, then Y will be observed). | Proficient · 12 ptsBackground, purpose, and hypothesis are present, but the hypothesis is stated as a question or the prediction is left implicit; background may rely on the lab manual alone. | Developing · 9 ptsThe hypothesis is vague or untestable, the background is a sentence or two, or the purpose is not stated. | Beginning · 5 ptsNo hypothesis, or the introduction is missing or copied from the lab handout. |
| Methods15 ptsA description of materials and procedure that another student could follow to repeat the experiment. | Exemplary · 15 ptsMaterials, quantities, equipment settings, and each step of the procedure are described in past tense paragraphs (not a numbered copy of the handout) in enough detail to replicate, including sample sizes, controls, and how variables were measured. Any deviation from the handout procedure is noted. | Proficient · 12 ptsThe procedure is replicable with minor gaps (for example a missing quantity or setting), or it is written in imperative form copied from the manual. | Developing · 9 ptsSteps are summarized so briefly that replication would require guesswork, or controls and variables are not identified. | Beginning · 5 ptsMethods are absent or describe a different procedure than the one used. |
| Results: data, tables, and figures25 ptsAccurate presentation of the data collected, with properly labeled tables and figures and a text summary of the key findings without interpretation. | Exemplary · 25 ptsAll raw or summarized data appear in numbered tables and figures with titles, axis labels, units, and captions; calculations (means, standard deviations, percent error) are shown or referenced; and the text walks the reader through the main patterns, referring to each table or figure by number. No interpretation appears in this section. | Proficient · 20 ptsData are complete and presented in tables or figures, but a label, unit, or caption is missing, or the text summary skips a figure. | Developing · 15 ptsSome data are missing or inconsistent with what the methods describe, figures lack labels, or the results text mixes in interpretation that belongs in the discussion. | Beginning · 8 ptsData are absent, unreadable, or presented only as unexplained numbers. |
| Discussion and interpretation25 ptsInterpretation of the results in light of the hypothesis, comparison with expected values or literature, and discussion of error sources. | Exemplary · 25 ptsThe discussion states whether the hypothesis was supported, explains the results with reference to specific numbers from the results section, compares them with expected or published values (cited in APA 7 format), identifies specific sources of error and their likely direction of effect, and suggests concrete improvements or follow-up experiments. | Proficient · 20 ptsThe hypothesis is evaluated and results are explained, but the comparison with expected values is general or error sources are listed without explaining how they affected the data. | Developing · 15 ptsThe discussion restates the results without explaining them, or attributes all discrepancies to 'human error' with no specifics. | Beginning · 8 ptsNo interpretation, or conclusions contradict the data presented. |
| Conclusion10 ptsA brief closing that states the main finding and its significance. | Exemplary · 10 ptsIn one short paragraph the conclusion restates the purpose, gives the key quantitative result, states whether the hypothesis was supported, and notes the significance of the finding, without introducing new material. | Proficient · 8 ptsThe conclusion summarizes the finding and the hypothesis outcome, but omits the key number or the significance. | Developing · 6 ptsThe conclusion is a single sentence or repeats the discussion at length. | Beginning · 3 ptsNo conclusion. |
| Format and citations10 ptsUse of the standard report sections, formatting, and APA 7 citations and references. | Exemplary · 10 ptsAll sections appear in the standard order with headings, tables and figures are numbered and referred to in the text, and every source (including the lab manual) is cited in-text and on an APA 7 reference list. Grammar and spelling errors are rare. | Proficient · 8 ptsSections and citations are present with a few format slips, such as unnumbered figures or a reference entry missing a DOI. | Developing · 6 ptsSections are out of order or merged, the lab manual is used without citation, or there are frequent grammar errors. | Beginning · 3 ptsNo section structure, no citations, or the report is largely unreadable. |
What the phrases mean, and how to show it
- “testable hypothesis with a prediction”
A statement that could be proven wrong, followed by a specific prediction in the form 'if X, then Y will be observed'.
Show it: End your introduction with two sentences: the hypothesis as a declarative statement, then the prediction naming the variable you will measure and the direction you expect.
- “replicable methods”
Materials, quantities, equipment settings, sample sizes, controls, and each step written in past tense paragraphs, with any deviation from the handout noted.
Show it: Rewrite the handout's numbered steps as past tense prose ('We added 5 mL of...'). Add quantities and settings the handout left implicit, and a sentence on anything you did differently.
- “labeled tables and figures”
Every table and figure is numbered, has a title and caption, and shows axis labels and units; the text refers to each one by number.
Show it: Open each figure and check four things: number, title, axis labels, units. Then search your results text for 'Figure 1', 'Table 1', and so on. Every one should be mentioned.
- “results without interpretation”
The results section describes the patterns in the data and shows the calculations; what the data mean belongs in the discussion.
Show it: Read each results sentence and ask whether it states what you observed or why it happened. Move every 'why' sentence to the discussion.
- “specific sources of error”
Named error sources, each with its likely direction of effect on the data, plus concrete improvements or follow-up experiments.
Show it: For each discrepancy, write one sentence naming the source (for example, heat loss from the container) and one saying whether it pushed your value up or down. Then one sentence on how you would fix it.
- “compares results with expected values”
The discussion sets your numbers against expected or published values, cited in APA 7 format, and explains the difference.
Show it: State your result and the accepted value in the same sentence with the percent difference, and cite where the accepted value came from.
Where papers lose points
- The hypothesis is written as a question or as a statement that cannot be proven wrong.
- The methods section is the handout's numbered steps copied in imperative form.
- Figures lack axis labels and units, which drops the results score to Proficient or below.
- Discrepancies are blamed on 'human error' with no specific error named and no direction of effect.
- Interpretation appears in the results section, or new data appear in the discussion.
- The lab manual is used throughout but never cited in the text or on the reference list.
What “Exemplary” looks like on Discussion and interpretation
The hypothesis was supported: the reaction rate at 30 °C (0.078 M/s, Table 2) was roughly twice the rate at 20 °C (0.039 M/s), consistent with the doubling per ten degrees reported by Varga (2019). Our values ran about 6% below the published figures, most likely because the water bath lost heat during transfers, which would slow the reaction and lower the measured rate.
An original example written for this page, not a student's work. Any names and studies in it are invented.
Questions about this rubric
Can I write the methods as a numbered list?
Not on this rubric. The top level asks for past tense paragraphs with enough detail to replicate, and it names a numbered copy of the handout as the thing to avoid. Use the handout as your source, but write what you actually did in your own sentences.
What counts as a specific source of error?
A named physical or procedural cause, with its direction of effect. 'The thermometer was read before the bath stabilized, so early temperatures were recorded too high' is specific. 'Human error' and 'the equipment was old' are not.
Does the lab manual need a citation?
Yes. This rubric treats the lab manual as a source like any other. Cite it in the methods and anywhere else you rely on it, and add a reference entry. Using it without citation lands the format criterion at Developing.