Before we invest $10 billion to fund new programs for preschoolers, let's get an answer to the $100 billion question: Does Head Start provide lasting benefits? Universal health care may top the wish-lists of many liberals this Christmas -- but universal preschool isn't far behind. President Obama is doing his best to play the role of Santa, bringing subsidized pre-kindergarten to a growing number of American families.

The president has called for $10 billion in new funding for preschool programs, and Congress is working to deliver. The American Recovery and Reinvestment Act included $5 billion for preschool and childcare programs. In September, the House passed a higher education bill that included an $8 billion "Early Learning Challenge Fund" to provide grants to states to expand subsidized preschool. The Senate is expected to follow suit.

These proposals are based on the belief that "investments" in early childhood education yield significant long-term benefits for children served. As President Obama himself promised, "For every dollar we invest in these programs, we get nearly $10 back in reduced welfare rolls, fewer health care costs, and less crime."

If the president is right, we should look forward to a safer, healthier, and welfare-free world sometime soon, thanks to our federal "investments" in preschool. In 2009, taxpayers will spend $25 billion on the federal government's 69 federal preschool and childcare programs.

Unfortunately, little is known about whether these programs work. One might think that Congress and the administration would be focusing on evaluating these programs' effectiveness before spending another $8 billion on preschool. Actually, there is reason to believe that they are instead ignoring empirical evidence that undermines the case for a new federal preschool program.

Consider the saga of the Head Start program and its national evaluation. In 1965, President Lyndon Johnson created Head Start, the first national preschool and childcare program serving low-income children. Nearly 45 years later, the federal government has spent more than $100 billion on it. With annual funding of approximately $7 billion, Head Start currently spends at least $7,300 annually on each of the 900,000 low-income children served.

For more than a decade, Congress has been trying to figure out whether Head Start has provided lasting benefits for participating children. In 1997, the GAO reviewed the available literature on Head Start's impact and concluded that body of research was inadequate for drawing conclusions about the program's effectiveness. This finding led Congress in 1998 to mandate a national evaluation of Head Start's impact on participants.

Seven years later, the Department of Health and Human Services released the preliminary findings of the national impact evaluation -- comparing the development of children served by Head Start with their peers who didn't participate in the program. In the critical area of cognitive development, the evaluation found that Head Start's participants experienced modestly positive benefits compared to their peers who weren't served by the program. Head Start children outperformed their peers in four out of the six cognitive constructs: pre-reading, pre-writing, vocabulary, and parent reports of students' literacy skills.

But the 2005 evaluation looked only at children's developmental progress after one year in Head Start. It didn't address the $100 billion question: Does Head Start provide lasting benefits?
This question would be addressed by future evaluations of the performance of former Head Start students and their peers through the end of first grade and third grade. Data collection for the initial study of first graders' progress was completed in the spring of 2006.

Three years have now passed. According to the HHS Web site, this project was supposed to be completed by March 2009. But the findings of the congressionally-mandated evaluation have never been made public.

One can't help but wonder: What's causing the delay? Former HHS officials have told me that they were briefed on the results of the first-grade evaluation in 2008. They report that the evaluation found that, overall, Head Start participants experienced zero lasting benefits compared to their non-Head Start peers by the end of first grade. These officials expressed little surprise that the report's release had been delayed.

Is the Department of HHS burying a damaging study? Perhaps there's a good explanation for the delay. But without raising the question, we won't know the answer. Before taxpayers "invest" another $8 billion in another preschool program, we deserve to know whether programs like Head Start are, indeed, making a lasting difference.

President Obama has said that his administration's only test for deciding what education programs to fund with our "precious tax dollars" will be whether it "works." It's time to find out whether he will keep his word -- even if it means bad news for one of liberals' favorite initiatives.

Dan Lips is a Senior Policy Analyst at The Heritage Foundation.

This article first appeared on FoxNews.com.