Pre Algebra Text book or online I have a kid who just started middle school. I would like to introduce them to pre algebra. I would like her to know the fundamental concepts. Just like "What is mathematics" book, if there is a book that can teach in kids language the algebra concepts then can you please inform me. On second thoughts a good workbook will also be helpful. thanks.
 A: Since you said "her", maybe Danica McKellar's books will be suitable.
A: As a 14 year old who has used AoPS for 4 years, I can say that the Art of Problem Solving book series has truly changed my life.  The AoPS books range from Pre-Algebra to Calculus, although they do have a separate series for smaller kids.  Their books are more competition inclined, so just beware of that.
The website, aops.com, offers many cheap online classes.  I have taken several of these classes (Algebra 2, Geometry, Precalc, etc.) and they are so much more helpful than the average group class, yet they cost less than a tutor.  aops.com also has many free Pre-Algebra videos that were made by Mr. Rusczyk himself, the founder AoPS.  
The AoPS books may seem to start from the basics, but actually accelerate very fast. They don't just skim on the surface of the topics as many schools do, but they go into the depth of each topic.  Many of the concepts in AoPS are much more advanced than the subject on the cover.  For example, many concepts in their Pre-calculus book are in normal Calculus classes.
If your child loves math and wants to do more, AoPS encourages students to actually do math competitions, although this is a little bit off the topic.  
If your child isn't able to do every single challenge problem in the Pre-Algebra book, don't worry.  It was built to be pretty hard; even in AoPS classes, instructors say that if you are able to do every single one of them, the book/class is too easy for you.  
