A study released early this year by the federal government's own Department of Health and Human Services concludes that the Head Start program "was found to yield no lasting results." (http://www.cnsnews.com/news/article/60001)
That hasn't stopped Congress from pouring billions of additional dollars from its Economic Recovery Act into the program, which the HHS touts on its own website. http://www.hhs.gov/recovery/programs/acf/hs-ehs.html
And why shouldn't it? It's becoming a familiar, albeit counterintuitive, corrollary among proponents of bigger government that any time a big-government program fails to meet its objectives it must be due to a lack of funding. If these kids aren't acheiving lasting results as a result of their participation is these programs, it makes you wonder what they are learning?