Should the US abolish the penny?
Yes, because it costs more than one cent to make, nobody uses it, and it is a dead weight on the economy which ends up in jars instead of in transactions, which is the entire point of currency. No ill effects come from abolition as Canada and Australia show, and the only reasons against getting rid of it are purely emotional.
The existence of the penny has helped raise a lot of money for charities. In 2009, school children collected over 15 billion pennies to combat leukemia — that’s $150 million dollars for blood cancer research and treatment.
On pure economical grounds, yes, it costs the US government more to make the penny, but the penny has emotional reasons to exist: "the lucky penny" you find on the street to make a wish or the penny you donate to charity in a jar to feel good about helping someone