1. SO YOU WANT TO WRITE A LAB REPORT
Name ___________________________________________ Date _________________ Period _________
SO YOU WANT TO WRITE A LAB REPORT
The sheets of paper that you turn in after each lab are, indeed, called a lab report. However, they do not often express a clear flow of ideas. Usually, they are just a bunch of questions about the lab to see if you grasped the concept. For example, if the lab was on Photosynthesis, the questions might be about the Calvin cycle, the parts of the plant cell, and so on. There is not any “story” to the questions though. They are not usually related. This is ok, but we can do better.
When scientists write a lab report, however, they are writing a story. They describe how they started, who the characters were, what they did, what they used, and what ended up happening. While there certainly are differences between creative story-writing and scientific writing, the overall goal remains the same: to tell another person what happened so that they can recreate it if they want to. With a story, you get to recreate it in your imagination. Remember that thing? You used it before you got your PS2, and you’ll have to use it again now that you’ve thrown your Wii-mote through your TV screen. In scientific writing, the reader has to be able to recreate whatever you did, but in real life.
In order to make it as easy as possible for another person to visualize what you did, scientists have adopted a common format for lab reports. Every report must include the following sections, in the order given.
I. TITLE PAGE – This page should be neat, organized, and contain the following information: your name, your partners’ names, the date you did the experiment, the title of the experiment (NOT the title of the lab – make up a good title of your own!), and where you did the experiment (e.g. “Groton, NY,” not “The lab table by the window on the left side”). Pictures are good if you’re scrap-booking, but not on a lab report cover page. Keep it simple.
II. ABSTRACT – This is a section that you haven’t used before in science. The abstract is a one- or two-paragraph summary of your entire report. It should contain your hypothesis, and a brief description of your methods, results, and conclusions. The abstract is the first thing in a paper, but it is written last. The purpose of it is to let a reader know what your paper is about without having to flip through and read your entire report. It should be concise and it should spoil the ending to your paper! It’s like a concentrated burst of science right at the beginning. BANG.
III. INTRODUCTION – This section should talk about why you are doing your experiment. What research led you to this point? Give some background information on your experiment, such as details on the reaction happening, the classification of the organisms involved, etc. Tell about what other scientists have done before you, and how you are going to build on their experiments. For example, if your experiment concerns the pH of the thylakoid space in light and dark, you might explain that you heard in class that the pH varies, and you want to find out if it is true. This section should be a few paragraphs long, and should explain to the reader anything they might need to know in order to read the coming pages. The last bit should contain your hypothesis, which is what you think will happen in the experiment. Remember, hypotheses are usually phrased “If ______, then I think _______.” Don’t dance around the point; state your ideas strongly. Do not use “I suppose” or “I might expect,” instead, say “I think that” or “I believe.” If you’re wrong, so be it, but be completely wrong! It’s ok to use “I” or “we” in this section.
IV. MATERIALS – Simply a list of everything that you used. Be specific. If you used a 500 mL beaker, say so. Don’t just say “a beaker.” Remember, anyone with a reasonable scientific mind should be able to scoop up your paper, and recreate your experiment. Don’t include really obvious stuff, e.g. “oxygen to sustain life,” or “shoes to keep feet warm.”

2. We added 200 mL of distilled water to the flask, write
V. METHODS or PROCEDURE – This is a set of step-by-step instructions that anyone with a reasonable scientific mind should be able to follow. This means that you don’t have to include stunningly obvious
details such as “remove the stopper from the flask before pouring out the molten sodium.” However, if you did something that isn’t standard laboratory procedure, or you feel that more direction would be useful, include it. This section is written in paragraph form, and NOT as a list of numbered steps. It is important to note that this is not a set of directions; it’s NOT telling the reader what to do, but rather telling the reader what you did. The passive voice is the easiest way to do this. Consider the example below. Instead of writing:
We added 200 mL of distilled water to the flask,
write
200 mL of distilled water was added to the flask.
Look what happened. The object of the first sentence (distilled water) becomes the subject of the second sentence. It replaces “we” as the subject, and now “the flask” is the object. The idea is to be as clear and concise as possible, while NOT giving the reader a recipe or set of directions. You shouldn’t use a lot of connecting words like “after that,” or “next,” because a logical, scientific reader can assume that if one sentence comes after another, that the events in that sentence happened after those in the first one. It might sound clunky at first, but give it a try. You shouldn’t be using “I” or “we” in this section.
VI. RESULTS – This section contains all of your data that you collected. It should be presented neatly in charts, graphs, tables, or paragraph format. Remember to give a label to all figures and tables. You should not attempt to interpret or analyze your findings; simply present them. Generally, you don’t just plop your data table in here. Convert the data into an easily-readable graph!
VII. CONCLUSIONS – This is the time to get excited, because you really get to stretch your scientific legs. You get to analyze your data, and make scientific conjectures as to why you observed what you did. Use information from your introduction to demonstrate what your data shows. Draw connections between your data and that of your classmates. Does your data support or disprove your hypothesis? Remember, a hypothesis that has been disproved is ok, just explain why things went another way. There are no “wrong” hypotheses. Note that the title of this section is plural, so you should arrive at more than one conclusion. You might also detail further experiments that you’d like to try, explain any sources of error that might affect your data, or connect information in your introduction to your results to attempt to explain them. It’s ok to use “I” or “we” in this section.
GUIDELINES FOR ALL SECTIONS
1. You should always write in the past tense. After all, you did the experiment in the past.
2. Do not equate the volume of your words with the content they contain. That is, you won’t necessarily write a better report if you write more. Conversely, writing too little isn’t good, either. The whole idea of scientific writing is to convey your point using the exact number of words needed, and no more or no less. That’s why there are no page limits to lab reports.
3. Always give numbers in metrics, and always include a unit. No naked numbers!
4. Make sure all charts, graphs, tables, figures, or diagrams are labeled. If you need to reference a chart, do so by saying “as figure 1 shows….,” and not by saying “in the chart below….” The chart might not end up directly below your sentence when you’re done editing.
5. Your reports must be neatly typed. Include a heading for each section (e.g. “Methods”)