WRITING GUIDE & STYLE SHEET

How to Write a Lab Report for your SSHS Science Classes . . .

 

Writing a scientific lab report is very different from other types of writing. It is more formal rather than conversational. It focuses on accuracy and precision, and it is very specific in its arrangement. Different areas of study, universities, and instructors may all use a similar but unique format to their lab reports. The format outlined and described below is the format you are to follow for writing lab reports for this class. Every formal lab report that you write will contain all ten sections. Each section is marked with a Roman numeral and the name of that section (e.g. III. Materials).

 

All sections except "materials" are written in complete sentences. You should always write a lab report in third person, past tense. Do not use the words "I, we, you, she, he, they..." For example, instead of writing, "I drew the cells," use the statement "Drawings of the cells were made." Another example would be to replace the statement: "I recorded the temperature of the solution and found it to be 70 degrees Celsius." with "The temperature of the solution was found to be 70 degrees Celsius."

 

I. Title

The title of your lab report should be as specific as possible. It should be clear and concise and indicate the general focus of the lab.

 

II. Abstract

This section should provide a brief summary of the lab. It should include what topics are being explored and what objective the lab is trying to accomplish.

 

III. Question:

What is the question you are trying to answer? That is, why are you conducting the lab?

 

IV. Hypothesis

This section should include your "educated guess." You should predict what you will find when you perform the experiment. You must also explain why you made the prediction.

 

V. Variables

Controlled, Manipulated, Responding variables should be listed. Refer back to the question to help identify these variables.

 

VI. Materials

List every piece of equipment you used in the experiment or lab set-up. This section does not need to be in complete sentences.

 

VII. Procedure

Use this section to identify the variables (manipulated and responding) and to identify the controls. If a procedure has been provided, you must refer to it in this section, e.g. "Please refer to procedures titled Diffusion and Osmosis Lab." If you are writing your own procedure, be sure to provide detailed, step-by-step instructions stating exactly what you did to perform the lab. An acceptable procedure has enough details and instructions so that anyone can perform the exact same experiment simply by following your lab report's procedure.

 

VIII. Data and Observations

This is where you will record any observations, measurements, or other data that you collect during the lab. It might be a chart, graph, drawings, or simply some statements you make about the experiment.

 

IX. Analysis/Conclusion

This section is worth a large portion of the lab report grade. This is where you should include such information as: What theory was demonstrated in this experiment? What do the calculations show? How was the purpose of the experiment fulfilled? Why does/doesn't this experiment work? How your results support or don't support your hypothesis. (Remember, one experiment doesn't prove or disprove, so avoid using those terms.) How could you improve the lab design? Is there another experiment you would perform to get further information or clarification? If your hypothesis is not supported, you must provide a revised hypothesis based on your data.

 

Refer back to the purpose of the lab to write this section.

 

X. Sources of Error

What are some specific sources of error and how do they influence the data? Do they make the values obtained larger or smaller than they should be? Do not use simple statements such as, "The balance was off." "I could have made a mistake." Those could be true, but we would like more thoughtful statements. This is where discussion of percent error, percent yield, etc. would happen.

 

How a Lab Report is scored . . .

 

Language :

1 point bonus – Lab reports should be written in third person past tense.  Personal pronouns like I, you, we, she, they… should never be used.  Example:  “The beaker was filled” instead of “We filled the beaker”.  Lab reports should not be written like a recipe or list of instructions to follow.

 

Title:

1 point  - The title should be meaningful; do not use “catchy or cute” titles; titles should be straight to the point; the title describes what the lab was about.

 

Abstract: 

3 points – This is a brief summary of the lab; what the lab was based upon; the objective of the lab; what the lab showed

 

Hypothesis: 

2 points - Educated guess; based upon research from some source, book, text,  journal…

 

Needs to: 1) make a prediction 2) tell why the prediction was made.

 

Example: Because light is necessary for photosynthesis, a plant kept in the dark will not survive. Example 2: If light is necessary for photosynthesis, a plant kept in the dark will die.

 

Materials:  

2 points - List of all the materials used in the lab.

 

Procedure: 

5 points – Explanation of what was done to test the hypothesis.  This must be detailed enough for someone (not in the class) to follow.  The experimental group and the control group must be clearly identified.  The independent (manipulated variable) and dependent variables (responding variable) also must be clearly identified.

 

Data: 

4 points – data table; 4 points - graph

 

Must include: 1) data sheet, 2) graph.  Be sure to include a title on each and make sure there is a label for the x and y axis.  Remember, use a bar graph for individual items, a broken line graph for progression (over time), a pie graph for percents of a whole, and box and whisker plots for data groups.

 

Analysis: 

6 points - This is the analysis of the data. Discuss the relationship of the dependent variable to the independent variable.  This relationship in the data should support/refute the hypothesis.  This is where evidence is mounted for the conclusion.  Stress data relevant to the hypothesis.  Use mean, standard deviation, median, &mode where applicable.  Also discuss any sources of error.

 

Conclusion: 

3 points - The conclusion always connects the data to the hypothesis.  The conclusion will always state “…the data supported the hypothesis…” or “…the data did not support the hypothesis…”  Do not use “prove”, ”disprove”, “correct”, “incorrect”, ”wrong”, or “right” when referring to the hypothesis.  The hypothesis should be restated in the conclusion. Also, if the hypothesis is not supported, a new hypothesis must be stated based on the findings of this experiment.