New at this, already some luck with these halves.

[renegade_7]

After reading some of these posts, I thought I'd buy a box and give it a try. I bought a $500.00 box and only through the first box in the order. Found these four and four more boxes to go. This could be fun. But why look for the S mint marks on all these halves?

 

[TxTim]

S is the proof indicator- all the 68+ JFK's that are proofs are San Fran minted.
You'll know them before you see the S by the mirror background and frosty foreground.
Congrats and good luck on the rest!