When reporting a measurement, the number of decimal places should reflect the precision of the instrument, which in this case is determined by the uncertainty. The uncertainty is $\pm 0.005$ grams, which suggests that the measurement is precise to the nearest thousandth of a gram (three decimal places).

Therefore, the correct way to report the scale reading is 8.000 grams. This shows that the measurement is precise to the thousandth of a gram, consistent with the uncertainty provided.

Would you like to know more details about how uncertainty affects measurements?

Here are some related questions:

1. How do you calculate uncertainty in multiple measurements?
2. What is the difference between accuracy and precision in measurements?
3. How do you determine significant figures in a measurement?
4. What role does uncertainty play in scientific experiments?
5. How do you propagate uncertainty in a series of calculations?

Tip: Always ensure that the number of significant figures in your measurement matches the precision indicated by the uncertainty.