The Art of Writing a Lab Report

Labs are the basis for our understanding of the key concepts in science. Scientific papers should be written in third person, and in a passive voice. What follows are guidelines for success in writing a quality lab report for most highschools.

1. Keep all data collected. Data is collected in ink. This is done to prevent experimenters from "modifying" data.

2. All reports should be written in pen on loose leaf paper or word processed. Write on one side only.

3. Your name, the names of all members of your laboratory team and the date the investigation was performed is to be written in the upper right hand corner of the first page.

4. An appropriate title for the report should be placed in the center of the first page of the report. This tile should not be goofy but more serious, unless otherwise instructed.

5. Each of the following sections of the laboratory report should be prefaced with the section names. You should put a space in-between each section.

Purpose- this is a statement of the problem to be investigated; why is the lab being done? It provides the overall direction for the investigation and must be addressed in the conclusion. Use complete sentences.

Procedure- this section should identify and name all experimental variables and briefly describe how the independent variables are controlled. Someone who was not present during the lab should be able to understand how the experiment was performed by reading it. Depending on your teacher be as thorough as needed. For instance if a teacher tells you to be very thorough add things like "gather all materials" and "clean up" as part of it; if thoroughness is not important, this can be omitted.

Data- data consists only of the quantitative and qualitative observations taken. No values obtained by way of mathematical manipulations or interpretations of any kind may be included. Only the numbers you observed. If you observed a change and calculated a difference, do not include this. Data should consist of as many trials as judgment would indicate necessary. The units for physical measurements (kg, m, s, etc.) in a data table should be specified in the column heading only; ask you teacher if you should use SI, Metric, or English unites. Data should be recorded to the appropriate number of significant figures and be presented in a data table.

Evaluation of data/Analysis- this section should include all graphs, analysis of graphs, and post laboratory calculations. State each formula and if necessary, identify the symbols used in the formula. If repetitive calculations are to be performed, substitute only one set of data into each formula and then construct a table of values for all additional calculated values. Be certain that your final calculated values are expressed to the correct number of significant figures. Do not show arithmetic calculations.

Discussion- in the discussion, do the following:

A) State relationship between the variables identified in the purpose in a clear, concise English sentence.

B) When a mathematical expression can be derived from the graphical analysis, write it, making sure to include the appropriate units. state the meaning of the slope and discuss significance of the y-intercept (when appropriate).

C) When your results differ from what is expected, provide a plausible explanation. would your answer have been closer with better equipment, better preparation?

D) When an error analysis is possible, discuss your percent error.

E) Answer any questions asked in the lab.

Conclusion- the conclusion is a short statement that answers the purpose.

This is meant to be general instructions on how to write a good high school lab report. Make sure to check with you teacher on what s/he wants. Good luck.