Below is a science fair project that my granddaughter did for 2006.
In it she took filtered water and divided it into two parts.
The first part she heated to boiling in a pan on the stove, and the second part she heated to boiling in a microwave. Then after cooling she used the water to water two identical plants to see if there would be any difference in the growth between the normal boiled water and the water boiled in a microwave.
She was thinking that the structure or energy of the water may be compromised by microwave. As it turned out, even she was amazed at the difference.