Just a side note on the conversation about math textbooks and teachers. I have worked with math book writers. And with the ones I worked there were two groups of experts involved - math education professors (the ones who teach future teachers how to teach math) and math professors. Majority of math education professors have not been in classrooms themselves for decades, but they still teach how to teach our kids and write textbooks for our children. However, I believe that the largest issue we are dealing is that there is no coherence in our educational system, the curriculum that teacher education program teach to future teachers does not align with the curriculum they will be expected to teach. And how could it be aligned, if states, districts, schools within districts have such a varied curriculums. Then the curriculum teachers are expected to teach does not align with any textbook 100%. In addition, our elementary school teachers are not math teachers, they may have minored in math, but they are not specialists. High school teachers are supposed to be, but what about middle school teachers? Research shows that the middle school teachers are just really left out, somewhat forgotten by the teacher preparation programs. If somebody is interested there is a report available online "Breaking the Cycle International Comparison of U.S. Mathematics Teacher Preparation.", I think the Executive Summary touches on many issues discussed here.
http://www.educ.msu.edu/content/sites/usteds/documents/Breaking-the-Cycle.pdf
