How Many Positions?

In the Sex Ed class the teacher says, "All right, class, I want you to go home and come back tomorrow with as many positions as you can think of for making sex."
The next day she says to Little Johnny in the back, "Well, John, how many positions did you come up with?"
Johnny says, "Seventy-three."
The teacher says, "Oh, my goodness...uh...very good, John, very good..."
She calls on Becky in the front and says, "All right, Becky, how about you?"
Becky says, "Gee, teacher, I only came up with one...where the guy just lays on top of the girl."
Johnny yells, "Seventy-four."