A Light in the Attic

I will start out by admitting that I am a huge Shel Silverstein fan. I remember when I was a kid, I performed in the church talent show by reading poems from this book. I read about four or five, but the only one I specifically remember reading was the one about washing the dishes.

I can't figure out why this book is challenged and his others aren't. Or rather, I can't understand why this book is challenged. Period.