Lab Format

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When scientists do an experiment, it is important that they keep a complete and accurate record of how they did their experiment, what their results were, and what conclusions were formed from these results.  In order to do this, they write up a lab report. While you are studying science at Bonney Lake High School, there will be occasions when it will be required that you write up a lab report.  The general format and descriptions of sections for writing a laboratory report follows. Final drafts of labs should be typed or written in blue or black ink.

The title for the entire lab should be written on the first line of the page. Two lines should be skipped between each section of the report. The title for each section should be written just inside the left margin of your notebook and the text or table for that section should start on the next line just inside the left margin as well. 

Title: The title should be specific or creative, telling exactly what you are studying.  If there is a title already given, you may use it.

Background:  (This section may not be included on all lab reports.) The background information includes all information you know before the experiment either through prior knowledge or research. This section goes from very general about the topic to very specific to your investigation.

Problem/Purpose Question: The statement of the purpose or problem should be simple, direct and always in the form of a question at the end of the background information. Both a manipulated and responding variable should be included in the question. Your entire report should be directed towards answering this question.  

Hypothesis: The hypothesis is  an educated guess as to how you think the results might turn out. It should answer your purpose question. The hypothsesis should be in the “If/Then/Because” format, with the "If" part about what you will do to the manipulated variable, the "Then" part about what you predict will happen to the responding variable, and the "Because" part should explain why you think it will happen that way.

Materials and Procedure:  List all of the equipment and materials that are needed to do the experiment, so that someone else could repeat the experiment if they wanted. Your procedure should tell exactly what you did and how it was done, again so that someone else could duplicate your work. It should be in a logical step-by-step list for clarity.  Brands, amounts, sizes and such details should be included. Include validity measures in your steps that help make your experiment more valid, be sure to include when and how you recorded your data, and repeated your entire experiment. The manipulated, responding and constant variables, as well as, experimental control should also be included.

Observations and Data: The data section is a record of quantitative experimental data in the form of charts, graphs, or tables. Your observations tell what actually took place and are a record of qualitative data. An observation is a description using one of your five senses and can include drawings. Your opinion or inferences should not be include in your observations.

Analysis:  This section is reserved for calculations and processing of data. Here you show all the calculations you make, using the raw data, to determine your values. These can also include calculations of averages (means) and percent error. Answers to pre-made questions may also be included in this section.

Conclusions:   This section begins by making a relationship statement about the variables being tested that includes data from your experiment to support what you say.  It should also include an explanation of why you think they did what they did. Then an example from the real world should be explained where the same results are seen. Some possible errors should be identified and then an explanation of how they could have affected the results should be included. Finally, a new question should be developed to test the concepts that includes both a manipulated and responding variable.