Experimentation 

Step 5 - Conduct your Experiment, Record Data and Observations

1. Follow your procedures to complete your experiment.  If you decide to change anything while you are doing the experiment record it in your science fair log book. 
2. Make sure that everything stays the same (control variables) except the one thing you change (manipulated variable.)
3. Make measurements and record your data (responding variable).  Use metric units whenever possible.  Record this data in a chart in your science fair log book.
4. Be sure you have enough trials.  Do your experiment many times.  The more trials the better.  Depending on cost and time 25-100 is great.
5. Everyday write at least one entry in your log book describing what you did, thoughts or ideas and questions you have regarding your science fair project.
6. Take pictures during your experimentation.  Focus on what is happening in the experiment, not on you.  Good pictures that show before and after are great ways to display your data.