Children's game.
"Ok, let's play a game. I'll say 'I one the sandbox', you say 'I two the sandbox', and we'll keep counting, k?"
"K."
"I one the sandbox!"
"I two the sandbox."
"I three the sandbox!"
"I four the sandbox."
"I five the sandbox!"
"I six the sandbox."
"I SEVEN THE SANDBOX!"
"This is getting boring."
"C'mon, just a little longer!"
<sigh> "Ok, I eight the sandbox."
"YOU ATE THE SANDBOX?!? HOW DID IT TASTE?"
Usually followed by the sometimes magical, sometimes disturbingly maniacal laughter of young children.