Piano Lessons Can Be Murder by R. L. Stine
Practice till you drop ...dead. When Jerry finds a dusty old piano in the attic of his new house, his parents offer to pay for lessons. At first, taking piano seems like a cool idea. But there's something creepy about Jerry's piano teacher, Dr. Shreek. Something really creepy. Something Jerry can't quite put his finger on. Then Jerry hears the stories. Terrifying stories. About the students at Dr. Shreek's music school. Students who went in for a lesson...and never came out.