How to Write a Lab Report for High School Experiments

In high school, hands-on labs teach students about scientific procedures and method. A crucial part of a lab is the proper writing of a lab report. Whether your experiment itself is successful or not, your lab is not complete until you document your intent, methods, and results in your report. Learning to write a lab report is a simple process, and once you get the hang of it, it will become second nature. Different classes may vary the requirements for the contents of the report, but most will follow the basic pattern below.

Title your lab. Sometimes the title will be assigned by the teacher, other times you will be asked to come up with your own. The title should briefly summarize the focus of the lab: for example, "The Rate of Osmosis through Semi-Permeable Membranes."

Compose your introduction. The first section of your lab report is called the "Introduction" or "Purpose." This section states what your experiment will attempt to do and how you expect it to turn out. State the theory or hypothesis that you are attempting to test, and add information about previous scientific studies or experiments that are relevant to your theory.

List your materials in the "Materials" section.

Explain your "Procedure." This section is a step-by-step explanation of your experiment as you carry it out. Write the steps in order, unnumbered, as a paragraph, without frivolous narrative. Include any variables and controls. Also add any safety information in this section, and any sketches or diagrams of your method.

Write your "Results." List the data that you collect, in narrative paragraphs or tables, or whatever format works for your particular experiment.

Make an "Analysis" of your information. This section is where you describe what happened during the experiment and whether the results turned out as you expected. Even mistakes or undefined results should be listed here - presume that everything that happened is relevant, and propose theories for unexpected results. Solve any equations brought up in the experiment. Explain any problems or complications that prohibited an action from occurring. Include graphs here. Also, inform the reader of estimations you made to come to your results and why you made those estimations.

Write your conclusion. In this section of your lab, you talk about the significance of your results. Your Introduction stated a theory. You used the experiment to test that theory. If the theory was disproven, discuss whatever information you learned from the experiment. Apply your experiment to real life by discussing an issue or problem relevant to your findings.

  • Note the teacher's individual instructions for lab-report assignments. You may need to note your lab station number or list partners or other specific data.
  • Always read through experiment directions thoroughly before attempting an experiment.
About the Author

Diane Todd holds a Bachelor of Arts in mass communication from North Carolina State University and is a former video and web producer for a North Carolina multimedia agency. She also spent several years as a media specialist/graphics designer for the Cumberland County school system in Fayetteville, N.C.