The mathstart books vary in length. I will talk about 3 books that we like. All books have suggestions on how to maximize learning from them inthe back.
We started with a pair of socks. Basically it is a story narrated by a sock. On each page he thinks he has found his pair in various places, washer, dryer, basket etc. but upon closer inspection he realised that each sock is a little different. I would usually ask my son, is this sock the same? What is different about this sock? Etc
After we had read the book every night for about a week I made cards with various different socks and had my son help them all find their pairs.
The second book we read was beep beep vroom vroom. It is about a girl who gets into her brothers toy cars when she is not supposed to. Her mom and dad help her line the up in a pattern just how her brother has them. (red, blue, yellow etc) everyone does the wrote pattern. But a different pattern is made several times. Once again after reading the book for a week I made my son some cards with differnt colored cars and had him do patterns our of them for me.
The third book, possibly my sons favourite, is No More Carrots. It is about a boy rabbit going shopping with his mom. He wants to buy more carrots because he loves them. And his mom points out that a certain shopper has fewer carrots, another shopper has the same amount and a third shopper has more carrots. This more, fewer, same thing is contiuned several more times with other things they buy… Worms, nuts etc. During this book I would ask my son how has more, fewer(less) the same etc. after a week of reading I would then introduce him to the signs greater than, less than and equals, I had him show me with homemade carrot cards which was had more, fewer or the same.
We havent gone through all the books yet. But I try and go through them one week at a time until he masters the concept in the books. Many of the books align with the standards on the IXL site. I borrow the books I can from libraries. I also like to shop at half.com and abebooks.com for good deals. And amazon has a buy 3 get 1 free promotion, so I get 4 at a time when I can.
I do try and keep the books in as pristine condition as I can so I can sell them once we move on.
Oh and I have seen that there are books you can buy that tell you how to use the mathstart books for lesson plans.
Here is also a bibliography of books that may be available to you through a library that cover the same concepts. I have not read any other books yet. But I do plan to check out a few.
http://www.mathstart.net/books/math_bibliography.php