How to Write a Lab Report

1. How to Write a Lab Report

2. A good lab report includes: • Title in the form of a question • Hypothesis • Materials list • Procedure steps—numbered list, not a paragraph • Data—usually in the form of a table; indicate the manipulated, responding and variables held constant • Conclusion—tells what you learned; should answer the question and be supported by the hypothesis.

3. Example: Tomato Growing Does Changing the Type of Water Produce More Tomatoes? (Notice that it is a title and that all major words are capitalized. Titles are centered at the top. The word “title” is not necessary!) Hypothesis: I think that feeding tomatoes mineral water will produce more tomatoes.This is left justified. Additional lines are indented.

4. Example: Tomato Growing Materials: Tomato plants (one kind) Pots and soil Mineral water Tap water Seltzer water Lemon water Grow lights Use two columns so list takes up less space.

5. Example: Tomato Growing Procedure: • Set up 12 tomato plants. Be sure plants are about the same size and health. Soil should be the same type and the amount of soil (size of container) should be the same. Label 3 pots “tap water”, label 3 “mineral water”, label 3 “seltzer water”, label 3 “lemon water”.

6. Example: Tomato Growing Procedure (continued) • Water the pots marked “tap water” with ¼ cup of water each day. Repeat with other plants but use the appropriate type of water. • Keep the plants under a grow light, using 16 hours on and 8 hours off. • The room temperature should be between 70o and 80o F. • When tomatoes are produced, count the number for each type of water. Continue growing and counting until the plants die.

7. Example: Tomato Growing Data Table:

8. Example: Tomato Growing Conclusion: Based on this experiment, I found that the type of water was not a significant factor in the number of tomatoes produced. The tomatoes fed mineral water produced slightly more tomatoes but the difference between tap water and mineral water was not significant. Conclusions do not contain data, procedure steps, hypothesis, or how you feel about the experiment.

9. If there are teacher questions after the lab… • The answers to the questions should be added after the conclusion. • Most labs have questions after them!

10. Speed Trap Lab • Use the remaining time to draft a lab report for the Speed Trap Lab. • Use all the steps outlined here. • This presentation is loaded onto my Teacher Web site for you to reference. • Final draft (for a grade) will be due next week.