The penny should be eliminated. Here's why:
Pennies cost more to manufacture than they are worth. Pennies are made out a copper shell and a zinc core. It costs about 1.8 cents for every 1 cent penny.
Many machines don't accept pennies. Vending machines,laundry machines, parking meters, or practically anything else won't accept pennies because they aren't worth the time to count, store, and transport them. Due to inflation, the penny is less valuable every year.
Instead of paying exact change, you would round to the nearest 5 cents for cash transactions. Countries who have already done so saw no prices rise, or charitable donations drop.
Getting rid of the penny is a good idea, because it will save the U.S. quite a bit of money discontinuing the penny.