Ghosts in the Gust Room: Horror Hotel, Part 1 is a novella written by R. L. Stine and Melinda Metz. It was first published in 1998 and is the thirty-fifth book in the Ghosts of Fear Street book series.
Description[]
A strange spirit from the past is haunting Joe and his grandfather at the Horror Hotel. Good thing the two of them found a spell that will get rid of the ghost. But that is not all the spell does.
It also makes Joe and his grandfather switch bodies!
Can Joe get back in the right body before he becomes the oldest looking eleven-year-old in history?