I have not seen Everyday Math, but I can tell you that the Dale Seymour Investigations series which many schools in CA use to use, is a Constructivist program.
This is why people have a negative knee jerk response to the notion of "constructivist math". Investigations is one of the reasons my children are homeschooled. I have compared the output expectations of Investigations and Singapore math very carefully and there is *no* comparison. Investigations is beyond a joke. And I'm not just talking about the number of problems or that Singapore actually teaches the standard algorithms. The depth and complexity of the problems is markedly different.
My personal understanding of "constructivism" is that it refers to what goes on in the learner's head and does not refer to the mechanism for getting there. I think the whole discovery learning thing is a misinterpretation of constructivist theory.
