Sharon Begley, science editor at Newsweek, doesn't have anything nice to say about education research. In a recent article, she refers to it as "second-class science" and "so flimsy as to be a national scandal."
I agree that there is a problem, but I don't think she's diagnosed it correctly.
There is a lot of excellent research in education. I spend most of my time reading basic scientific work and trying to understand what it means for classrooms and for policy, and much of what I draw on is education research.
There is, however, also a good deal of dreck.
There is a certain amount of poor science in other fields as well. Go to the psychology section of a large book store and you'll see plenty of nonsense. Books with crazy suggestions on dieting, love, self-actualization, and so on.
The difference between psychology and education is that psychology, as a field, is more vigilant in its self-regulation, particularly through its professional societies.