Description Sight words are common words that appear again and again in your children's reading material. Knowing these words "by sight" is essential for reading fluency. Children learn to easily recognize these words in Bob Books Sight Words. Consistent short vowels and simple stories mean children sound out (decode) most of the story, and must memorize only three sight words per book. With plenty of repetition and context clues, your young reader will quickly master early sight words.