Seeking a Math Challenge

My 8 year old is in third grade and has just started multiplication in class.  To say nothing against her teacher or her school, my wife and I have gotten the message from our daughter that the math is a bit easy.  She doesn't seem bored nor does she ask for more, but she breezes through her math school work with no problem at all.  Knowing her as a child, we decided to get a math book for her to work on in addition to her school math work.  We went with the following book:

The book itself isn't a challenge book.  It's a standard third grade math book, but it allows our daughter to jump ahead to topics they haven't covered yet in school.  She's definitely ready and was super excited when the book arrived.  It didn't take any coaxing on our part at all to get her to test out the book.  As soon as she was done with her homework, she jumped right into it!  We'll have to see how it goes.  If she breezes through it in a couple of months, we may get the fourth grade version of the book.  

Parenting is tough, but if you're a parent, you already know that.  Watching your child struggle and not knowing what to do to help can be very frustrating.  A child struggling to understand a concept is tough, but so is watching a child struggle to be challenged.  I wouldn't say our 8 year old is there yet, but I'm seeing a few signs that this is a possibility in the future.  My wife and I are trying to be proactive.  Are we doing this right?  Maybe.  Maybe not   But we're trying and we'll continue to research the best methods to challenge our daughters if they need a greater challenge in their education.