When you get a bit sick of the boring old 'Awkward Turtle'
Used by putting one hand on top of each other and gesturing the thumbs forward (signifying the awkward turtle.) Then take your two hands into fists and bang them together (the erm, baby making) and finally keep your hands in fists but take your thumb and pinky out and move forward (signifying the babies.)
Put it together fast and you get it! :D
Boy: Hey, erm I like you.
Girl: I er, like you too.
Boy: Awkward turtle...!
Girl: Awkward turtle equals awkward babies!