This is a classic and so innocent at the same time.
The 2nd grade teacher that I've been subbing for is doing a "Favorite Book" lesson. Each student brings their favorite book and each day one book is chosen. We read the book, then the student go back to their desk and write a couple of sentences about the book and draw a picture about the book. The teacher collect these papers for a book she's putting together.
Yesterday we read the book ... they did their paper... I collected them.
Today I was moving them on the desk and I glanced a the top paper.
The student had written ....
"I lick the hole boob."
I just sat there and laughed ...