The values depend very much on the coins' dates.
1963 and 1964 halves are 90% silver and are worth at least $6-$7 retail as of 06/2010.
1965-68 are 40% silver and are worth at least $3.50
No 1963 Kennedy half dollars exist. 1963 is the last year of the Franklin half dollar. 1964 is the first year for Kennedy.
1963 is a common date for half dollars and the value is primarily for the coin's silver content. At present, it's worth around $11.
If it shows any wear at all the value is about $6.00 just for the silver. All Franklin half dollars (1948-1963) are considered common.
So many 1968 Kennedy half dollars were made and saved the value is just for the silver, about $6.00
So many were struck, if it shows any wear the value is for the silver, about $11.00.
In 1968 the Kennedy half dollars were still struck in 40% silver so it has the silver value only, about $2.50. The gold plating was NOT done at the Mint and adds nothing to the value.
So many were struck, if it shows any wear the value is for the silver, about $11.00.
Franklin half dollars (1948-1963) are not rare or even scarce so if the coin has any wear at all, value is just for the silver about $11.00.
20 half dollars have a face value of a $10.
All US half dollars minted from 1948 to 1963 are called Franklin halves because they carry a picture of Benjamin Franklin. There's more at the Related Question.
No US silver dollars were made after 1935, look at the back of the coin for 'Half Dollar'.
5-3-11>> If it shows any wear at all the value is about $15.00 just for the silver. All Franklin half dollars (1948-1963) are considered common.