RB-1 and the Mystery of the Letter R is a children's picture book that teaches children ages 3-7 about r-controlled vowels in a book that is entertaining and brightly illustrated. Teachers, parents and kids agree -- RB-1 is a fun way to lay a strong foundation for reading and phonics for kids ages 3-7. Based on computer-assisted phonetic analysis of 10,000 of the most frequently used words in popular literature, RB-1 Learns to Read is a serious phonics lesson hidden beneath a seriously fun and enjoyable book.