Senior Class Trip

In April of 1970 many of the members of the THS senior class took the traditional class trip to Washington, D. C.

There’s quite a mystery here. Two of our class members appear twice in this picture!
Can you identify them? Does anyone know how and why this was done?
(This is the entire picture. Scroll down to see two larger views.)
(Point to a face to see the name.)
(Point to a face to see the name.)