The Council for Exceptional Children generated a graphic that allows one to see the relative US federal funding for research in various areas. It’s a pretty clear indication of the importance attached to addressing the improvement of education, no? I’ve linked a larger version of the file to the image at the right. It’s suitable for downloading.
To be sure, there are some funds in the NIH and NSF research budgets that go toward educational research. For example, some of the funds from the National Institute of Child Health and Human Development fund research on Autism and Learning Disabilities. I do not know what proportion of those budgets are devoted to such educationally relevant topics, but I bet that it’s a small proportion.