Don't worry, MegMeg. The companies that sell the curricula sponsor their own research teams that conduct valuable research on the validity of the curricula. I'm sure it's all on the up and up.
It's worse than that. The research is often poorly designed by the people who developed the curriculum. Oh, the bogus studies I have read. Common mistakes include assumptions that our method is better (and no control group), an improper control group, and improper use of statistics. Not to mention drawing sweeping conclusions from poor-quality data.
The authors are not necessarily mathematicians, engineers, or scientists, either. For example, peruse the author lists for
Everyday Mathematics. I went through the authors listed for the Grade 2 books. There were biographies for 8; four were educators, two were neither educators or STEM professionals, and two were mathematicians (no engineers or scientists listed). BUT one of these two stayed in the education field for his entire 31 year career.
I couldn't find anything about the other two --- including no citations on Google Scholar outside of EM. Doesn't fill me with confidence.
