Book 3 of this series builds on the others by helping children master phonics. Take a look at what this parent had to say about this book in the series:

"Simply the best language/phonics book for young kid. I found out a little late about this book, so based on my kids reading abilities I start with Explode the code(ETC) 3. My daughter reminds me to sit with her to do atleast 1 Lesson everyday. I am usually very lazy to write reviews and take time to do it. But I am really very thankful to the makers of this product and currently back at Amazon for buying further version. I am on the fence to buy ETC 1 and 2 as well, definetely 4 and above for sure. If in doubt, I would say just buy one and not the whole series until you are really sure, thats the way I go. For now, I am having difficulty to make my kid stop at one lesson everyday. I dont believe in rushing the book in 1 day. Practice makes perfect. I like the way the lessons are structured as well. Before this I used to purchase kumon workbooks for my kids, but I guess I will stop that, as kumon is colorful but not result oriented compared to ETC, just my honest opinion."