Andrew's school had a Science Fair on 3/4 evening and 4th. - 6th. graders displayed their studies.
Andrew joined the fair, displayed his study to find which way is the best way to shine dirty penny coins and here is his display on the day. 
Daddy helped little bit but this was all his research himself and displays were all typed and prepared by himself too.

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Science Fair and Andrew in front of his presentation.

This is what he has done to find the best way to shine dirty penny. 

And, this is his conclusion.

 Andrew at Science Fair with dad and grandma. 

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