Dona Herweck Rice 
In a Box [PDF ebook] 

You can sit in a box. You can stand on a box. Learn the difference between "in" and "on" with this high-frequency word book! Perfect for beginning readers, this book teaches these 2 high-frequency words: in and on. The simple, repetitive phrases are accompanied by clear images that support the text to aid in memorization. The bright images, rebus pictures, and easy-to-read text make the book appealing to young learners and older emergent readers. Children will learn essential Fry sight words and gain confidence as readers as they learn to read independently and with joy.