We did all 3 primer books for the Explode the Code Series. My 5 year old daughter did great with books A and B but by book C she got a little bored with the repetition in each book.
Book A goes through letters b, f, k, m, r and t.
Book B goes through letters p, j, h, s, n and d.
Book C goes through letters c, l, g, w, y, v, z and q.
Each book contains about 10 activities per letter. They say the teacher's manual is required to properly use the book but we used it just fine without it.
Because the pages are all in black and white and the activities for each letter repeat so much, I would rather recommend BJU Phonics for K4 and K5 which I think is a much better program overall. But if your child enjoys extra writing and phonics practice, these make great additions to any curriculum.
The Get Ready For the Code books are great because they have multiple pages for each letter unlike other letter books I've seen. They use a lot of repitition which works well. My boys love doing them. I did notice that the pages of the B book are a little lower quality than the pages of the A book.
I didn't know what to expect with this book, but I've heard good things, so I thought we'd give it a try. I'm homeschooling my 3 kids and needed something for my "Young 5's" kid. He was struggling with the curriculum I bought, it didn't give enough practice on each letter sound; the pace was too fast for him. He and I both love this book. When I get it out he says "Yay, I love this book 'cause I'm SOOO good at it!" I love that! After trying many phonics programs like Hooked on Phonics, Spectrum Phonics, Red Plaid books, BOB books, Starfall, and others that just didn't work for my older 3rd grade son who is still struggling, I wanted to give my other kids a better start. I am feeling much better about this one!
My almost four year old daughter has loved doing the Get Ready, Get Set, and Go for the Code workbooks. It has really helped her with writing her letters and she loved all the activities in each section. I am definitely glad that we started at this level for her as it has given her such a great sense of accomplishment to have simple activities to do while working on her letter writing and sounds.