The following section is an excerpt from the example laboratory report, titled Proper Inflation of a Basketball. (The entire example report is available in either  Microsoft Word Format for printing, or  HTML format for online viewing.)

Conclusions

We have determined the optimum number of strokes of a hand pump needed to properly inflate a basketball. We have found that 12 strokes of our pump inflates our basketball so that it rebounds to within 62 ± 6% of its original height when dropped. Inflating the ball raises the pressure of the air inside it and gives it additional elasticity. On this basis, we have devised an method for determining the correct number of strokes necessary to inflate a basketball that can be used with any hand pump, if the volume of the air it compresses in a single stroke can be determined. Our results are valid for a temperature of 70 ° F. Extending our results to other temperatures would require additional analysis, measurement, or both. Repeating these tests with basketballs made of other materials would confirm our assertion that the material of the ball has little effect on its rebounding once it is fully inflated.

Note what's here:

• Numbers. If you get a numerical result in the data and analysis section, re-state it in the conclusion.

• Editorial comments. If you have an opinion about how long the lab took, how well the equipment worked, etc., express it to your instructor directly.
• "I learned a lot about...". If the lab was well designed, you did learn a lot, but that is not a valid conclusion. Limit your conclusions to those that you can support by your data.