The 5 Finger Rule 

Open the book to the middle.  Choose a full page of words.  Read the page out loud. Hold up a finger each time you come to a word you don't know or understand.

Girl Reading a book

 1
 
Hold up one finger (your thumb):
Thumbs Up!  You knew all but one word!  This book will be pretty easy for you.
 2
 
Hold up two fingers (thumb, first finger to make an "L"):
"L" stands for Learning.  You might need some help, but it will be a good learning book for you.
 3
 
Hold up three fingers (3 middle fingers to make a "W"):
"W" is for Warning.  You can read this book, but it is a warning that it might be frustrating and you may not enjoy it.

  4 

 
Hold up four, five or more fingers
This is a stop signal.  This would be a good book to stop reading by yourself and start reading with a buddy. 

  5

 
Find someone who can read this book with you or look for another book you will enjoy by yourself.