The Key to Surviving Summer - Sandi Van - Bog

It's the summer before sophomore year, and Moe is stuck in the middle of Nowhere-ville, in a broken-down cottage on Lake Ontario with no one her age for miles. Her neighbor's grandson, Zeke, definitely doesn't count. He is only eight, but desperation and loneliness force Moe to follow Zeke on his adventures. After a nasty storm, Moe finds a strange key and begins having visions of a girl roller-skating at sunset and then disappearing into the lake. Moe and Zeke comb the shoreline looking for clues, but when his grandparents find out, they forbid Zeke from spending any more time with Moe. Faced with even more isolation and increasingly vivid visions, Moe must figure out what happened to the mysterious girl and why it forced her temporary hometown into silence.