He needed a way to get Sarah out of his life. She dominated the school and frequently either insulted him and his friends for just minding their own business, or encouraged the football team to do so.
Then he had an idea... "I wish Sarah McMillan was a Freshman," Jon said. If Sarah was Zoe's age...she'd be too young to be head cheerleader...in fact she'd be too young to be a cheerleader at all, and...he and Karyn would be older. But ultimately, it wouldn't hurt her at all. The stone glowed, granting his wish.
But unknown to him, Sarah would notice that she was different, even though he didn't specify her to.
Meanwhile, at the McMillan house ..