Lab Report Writing

1. Lab Report Writing Leonard M. Fischer Plantation Middle School Plantation, FL

2. Parts of a Lab Report • Problem Statement • Background Information • Hypothesis • Experimental Design • Identify Variables and Constants • Data Table • Data Graph • Conclusion

3. Problem Statement • Identify the problem the lab is trying to answer. • Although called a “Problem Statement” it should be worded in the form of a question. • What was the problem statement in our gummy bear lab? • Example: “What will happen to a gummy bear when it is soaked in water overnight?”

4. Background Information • In order to make a hypothesis (which is an EDUCATED guess), you must have some background information on your experimental topic. • Example: Knowing what a gummy bear is made of, would help us predict what will happen if the gummy bear is soaked in water. • Let’s do some research and see what we find… • Gummy bears are made mostly of “Gelatin.” • When soaked in water, Gelatin absorbs waster and increases in size.”

5. Hypothesis • A hypothesis is an educated guess as to what will happen in your experiment. • It is based on the background information or research. • It should be worded in the form of an “If – Then” statement, where the “IF” is the independent variable and the “THEN” is the dependent variable . • What is our hypothesis in the gummy bear lab? • If we soak a gummy bear in water, then it will absorb some of the water and increase in size.

6. Experimental Design Materials: List all materials needed to do the lab. What materials did we use in our gummy bear lab? Procedures: List all steps to be followed in doing the lab. Do not skips steps or make assumptions that people will know how to do it. What steps did we follow in our gummy bear lab?

7. Identify Variables and Constants Independent Variable: Identify the variable manipulated by the person doing the experiment. What was the Independent Variable in the gummy bear lab? Dependent Variable: What changed as a result of the change in the independent variable? What was the Dependent Variable?

8. Identify Variables and Constants • Constants: What possible variables were kept constant during the experiment? • What did we keep constant in the gummy bear lab?

9. Data Table • You should include a copy of your data table in your report. • Usually, your original data is handwritten in your lab field book or notebook. • You should be typing up a clean lab report with a clean data table in it.

10. Data Graph • You should include a graph of your data. • Depending on the type of lab and the data collected, you may be using either a bar graph, a line graph or a circle (pie) graph. • What kind of graph would we have used in the gummy bear lab? • Follow the rules for labeling your graphs. For example, independent variable on the x-axis, dependent on the y-axis, full title, etc.

11. Conclusion • Conclusions should follow the “claim-evidence-reasoning” format. • Claim – Basically, this is restating the hypothesis. What did you “claim” would happen in your hypothesis? • Example: The claim in our gummy bear lab was that the bear would absorb water and get bigger.

12. Conclusion • Evidence - What evidence did you gather during the experiment that supported your hypothesis? Example: The data collected in my experiment showed that the gummy bear had a volume of 2 cm3 before it soaked in water. After soaking in water for 24 hours, the volume increased to 16 cm3.

13. Conclusion • Reasoning – The reasoning links the claim and the evidence. It is the explanation as to how the evidence supports, or does not support, the hypothesis. • Example: The data showed that after being soaked in water overnight, the gummy bear increased in volume from 2 cm3 to 16 cm3. In addition, our research indicated that gummy bears are made mostly of gelatin, and that gelatin is known to absorb water. I also noticed that while my gummy bear got larger, the amount of water in the cup decreased. Therefore, I can conclude that the missing water was absorbed by the gummy bear, and that was the reason the bear got bigger.

14. Conclusion • Recommend Improvements: The final step is to recommend improvements to the lab, or further studies which the lab suggests should be conducted. • What are some possible sources of error in the lab? • What additional investigation(s) do the results lead to? • This is especially important if your hypothesis is not correct. You may need to rethink your hypothesis and recommend a different experiment or study.