This fun and entertaining activity can be used in reading and language art centers or as seatwork to help review common core high-frequency words. The words in this book are from the Pearson Reading Street Kindergarten Series. This activity also reinforces number and letter recognition. Children find the number in the code box and write the letter above it on the short lines. Once they have each letter of the secret code written they write the whole word on the long line. For further practice children can write the words on the back and put them into a sentence. For fun they could find out the code for their name.