IB/AP Biology, IB/AP Chemistry, IB/AP Physics

IB/AP Environmental Science, IB Anatomy & Physiology


Laboratory write-ups should be typed (or neatly written on lined, non-spiral bound paper).  Clearly label each of the eight headings, exactly as shown in this format guide.  Write all portions of the lab in complete sentences. 


I.                    Title

·         Write the title of the laboratory experiment at the top of the page.  You are encouraged to be creative and original!


II.                 Purpose  [Planning (a)]

·         State in your own words  the problem or research question.  Describe the problem and define any terms included in the problem statement.

·         Clearly list and state the following variables:

Controlled variable:  The variable that remains constant in all parts of the procedure.

Independent variable:  The variable that you manipulate.  The data for this variable will be placed on the “x” axis (horizontal line) of your graph. An example would be “time in minutes.”

Dependent variable:  The variable for which you collect resulting data.  The data for this variable will be placed on the “y” axis (vertical line) of your graph.  Some examples are “substance produced,”  “substance used up,” or “degree of color change.”  Be sure to identify appropriate units.


III.      Hypothesis  [Planning (a)]  (A prediction or educated guess regarding the outcome of the lab.  It must be directly related to the research question and explained, quantitatively where appropriate.)

·         Write your hypothesis before you begin the laboratory.

·         State clearly what your expected data might be and why you expect these results.  Use a rational explanation.  If appropriate, include a proposed relationship between two or more variables (i.e. “if ‘a’ is done, then ‘b’ will occur”). 


IV.      Materials  [Planning (b)]
·         List, in columns, all appropriate apparatus or materials that are selected to conduct the lab.

·         If needed, draw diagrams of your apparatus. 


V.        Procedure  [Planning (b)]

·         Write the lab procedures prior to performing the lab.  The teacher will provide specific guidelines for each lab activity. 

·         In your own words state specifically the designed procedures, in numbered steps.  Your method must allow for the control of variables and the collection of sufficient relevant data.


VI.       Data Collection

·         Record raw data with precision, using correct units, during the lab.  Your data may be both qualitative and quantitative.  Explain uncertainties where necessary.

·         Use a well-organized chart or table when collecting data to allow for easy interpretation.

VII.      Data Processing and Presentation  (Process raw data correctly.  For example, a laboratory drawing would be considered data collection, but the accurate labeling of the drawing would be processing.) 

·         Present the processed data appropriately in order for it to be easily interpreted.  Where relevant, take into account errors and uncertainties.  When quantitative data is collected, it should be presented in a graph.  Clearly show all necessary calculations.   Make sure to label each axis correctly and include units!  (Remember, the independent variable is placed on the “x” axis and the dependent variable is placed on the “y” axis.)

·         Answer specific lab questions in section VII.  They will help you to think about what you observed and what your data might mean.


VIII.     Conclusion & Evaluation  (This is the MOST IMPORTANT section of the lab report.  Your conclusion section should be one to two pages in length, consisting of at least three paragraphs which address the following three bullets.) 

·         Formulate a valid conclusion based on the correct interpretation of the results. Explain your reasoning and compare your actual results to your original hypothesis.  Where appropriate, compare your results with literature values (what you have previously read).

·         Evaluate the procedure and subsequent results including your apparatus, materials, and methods utilized.  Include an explanation of limitations, weaknesses, or errors. 

·         After identifying weaknesses, state realistic suggestions to improve the investigation.
































Revised September, 2002