Lab report format
01 // Why the format matters
A lab report format exists so someone else could read your report and understand exactly what you did, without watching you do it. Each section has a specific job — mixing them together (like writing your conclusion inside the procedure) is the single most common reason a grader marks points off.
Not every teacher uses the exact same section names, but the order and purpose below covers the sections that show up in almost every version, from a one-page worksheet to a full formal report.
02 // The sections, in order
1. Title and question
Name the experiment and state the specific question it answers.
2. Hypothesis
Your if-then-because prediction, written before you ran the experiment.
3. Variables
State the independent variable, the dependent variable, and the variables you controlled.
4. Materials and procedure
List what you used and the numbered steps you followed, in enough detail for someone else to repeat it.
5. Data and results
Your data table and graph, showing exactly what was measured — no interpretation yet.
6. Conclusion
State whether the data supported your hypothesis, explain why using your data, and note any sources of error.
03 // Common mistakes
- Writing the conclusion in the results section — results state what happened, the conclusion explains what it means.
- Forgetting to state whether the hypothesis was supported or not supported, in plain words, at the start of the conclusion.
- Listing "human error" as a source of error with no specifics — a grader wants a real, specific limitation, like "the thermometer could only be read to the nearest degree."
04 // Questions people ask
Does a lab report conclusion need to say the hypothesis was right?
No. A conclusion that says the data did not support the hypothesis is just as complete as one that says it did, as long as you explain what the data actually showed and why.
What goes in the results section versus the conclusion?
The results section presents the data itself — tables, graphs, and observations — with no interpretation. The conclusion is where you interpret that data, connect it back to the hypothesis, and discuss sources of error.
How long should a middle school lab report be?
It depends on the assignment, but a typical middle school lab report runs one to two pages covering each section briefly; high school and AP-level reports are usually longer and more detailed, especially in the discussion of error sources.