Ch 1: How did Tom distract Aunt Polly when she found him eating jam?

Tom distracted his Aunt by pretending there was something behind her and promptly scrambling over the fence.

“Well, I know. It’s jam—that’s what it is. Forty times I’ve said if you didn’t let that jam alone I’d skin you. Hand me that switch.”
The switch hovered in the air—the peril was desperate—
“My! Look behind you, aunt!”
The old lady whirled round, and snatched her skirts out of danger. The lad fled on the instant, scrambled up the high board-fence, and disappeared over it.