The earlier coins are made of silver, as noted, which makes them rarer. An uncirculated one could be $2, but that's probably not worth running to eBay for. Kennedy bicentennial half-dollar coins ...

The half dollar is one of the most popular U.S. coins to collect. Though many aren’t worth more than their face value, older half dollars often hold value due to the silver in their composition ...

and silver was watered out of production by the early 1970s. Check Out: 4 Kennedy Half Dollar Coins That Are Worth Up to $150K Learn More: 5 Things You Must Do When Your Savings Reach $50,000 ...