Why does a Quarter have 1776-1976?

Answer 1

During the Bicentennial celebrations in 1975-75, the Mint issued billions of coins with dual dates 1776-1976 to honor the country's 200th anniversary. As you can see on the back, they also had special designs - a drummer boy on the quarter, Independence Hall on the half, and the Liberty Bell and moon on the dollar.

These coins are not scarce. In fact, so many were minted and so many were saved as keepsakes that they really don't have any extra value unless they're in proof or uncirculated condition.