We've used Teach Your Child to Read in 100 Lessons with 4 of our 5 children (the 5th is 2 years old). Starting at 3, they generally completed the book by 4-4.5

We've used Teach Your Child to Read in 100 Lessons with 4 of our 5 children (the 5th is 2 years old). Starting at 3, they generally completed the book by 4-4.5, one took until he was 5. After they finish the book, the authors have a list of recommended books for the kids to read next. It's a good list, but one other source we added were travel brochures. Anytime we stopped somewhere on a family trip, we'd load up on all the brochures of things to do in the area. My 9 year old is the oldest of the group, she's completed the Chronicles of Narnia, Anne of Green Gables, and the Little House Series each multiple times. Our 8 year old just finished reading the "Boy Who Harnessed the Wind" and just asked me for 100 feet of copper wire....our 6 year old wants to go to Round Rock, TX - his favorite brochure and our 3 year old is on lesson 40... if it were just one kid, I'd say it was just luck. But the book really works. And each lesson takes between 10-15 minutes. If you figure over the course of a year, you're spending roughly 25-40 hours on developing an independent reader, it's a no-brainer.