When in a store purchasing some Magic Tree House books for my son I was asked what I liked about them so much. My response was: they are perfect for kids. They provide enough of an in depth story to satisfy their curiosity. They are provided with enough of a drama to understand the struggle and/or the force of good v. evil - which feeds the soul of every person; particularly children. And they are innocent and free from sexuality and violence. These stories, every one of them is written from the heart and it translates!
My son couldn't wait for the next "tree house"...this is a wonderful story with just enough suspense so as to engage and invest him but without putting any pressure on the life force or immune system...great for bedtime reading.