Responses to a query on the NACAC listserv about a student who was interested in Astrobiology:

What is an astrobiologist and how do I become one?

Here's the Astrobiology Index.

It looks like a solid foundation in the physical and biological sciences as an undergraduate is necessary. She could probably put together her own major at a forward-thinking university that offers introductory courses in all the branches of biology, chemistry, astronomy & geology. She should consider what her strength/ interest is for her “home” science as the astrobiology centers are interdisciplinary but do have different leanings. Have her look at the research interests of the professors of likely-sounding courses. (This is the same sort of advice I give to someone who wants to be a primatologist or a herpetologist, both of which tend to be graduate degrees that require a solid grounding in biology.)

George Mason offers one of the best programs in the field, with close ties to NASA's offices here in the DC area (Greenbelt, MD). "Our expertise is particularly in the computational science arena - using super computers and microarrays by biologists and astronomers to analyze data from satellites, probes, etc. Also closely linked to geology, Mason developed the first college of Computational Sciences in the U.S. At the undergraduate level, your student could either focus in on one of the related minors and participate in the developing minors and research opportunities in the field, or, if more technically minded, take our new major in applied computer science in the school of Inforamtion Technology and Engineering. That program is designed to train science students who hope to move into interdisciplinary arenas like this one, and the concentration that it was intended for is the geophysics/astrobiology graduate study. Since there are few undergraduate programs preparing students to move on to graduate study in these fields, this program was developed in an unusual collaboration between computer science, geology and biology faculty."

Rensselaer Polytechnic Institute (RPI)] has a minor in the Physics department - http://www.rpi.edu/dept/phys/UnderGrad/main.html

The University of Rhode Island lets upper-class undergraduates study under Oceanography

University of Texas at Austin

Cornell University

UCLA

Agnes Scott in Atlanta (women's college) has an excellent astronomy program, but I don't know about astrobiology

These are a couple schools that have such a program:

Arizona State

Colorado

Penn State

Given its connection with NASA, the Florida Institute of Technology might be a good place to look.