Various NASA competitions
National Space Club various opportunities and scholarships
Click here for National NASA opportunities. Some are webinars, but many take you for a week to Johnson Space Center.
The Summer Science Program (SSP) is a residential enrichment program in which gifted high school students from around the world complete a challenging, hands-on research project in celestial mechanics.
Six week research institiute at MIT. Each summer, 80 of the world's most accomplished high school students gather at the Massachusetts Institute of Technology (MIT) for the Research Science Institute (RSI). RSI is the first cost-free to students, summer science & engineering program to combine on-campus course work in scientific theory with off-campus work in science and technology research.
Not necessarily astronomy related, but...
The UC Davis Young Scholars Program is a summer residential research program designed to expose approximately 40 high achieving high school students to the world of original research in the natural sciences with emphases on the biological, environmental and agricultural sciences. To be eligible for the summer of 2013, students must be currently enrolled as sophomores or juniors in high school. Each student will work on an individual project and prepare a journal quality paper and symposium presentation about their work. In addition to scientific research, the UCD-YSP strives to introduce participants to the climate and culture of living and working on a university campus.
The UCSB (Santa Barbara) Research Mentorship Program is the ideal learning opportunity for the selected students because each chooses a research discipline and is partnered with a UCSB researcher who is a leader in their field. This six-week program accepts high-achieving high school students from all over the world and offers them a variety of interdisciplinary projects to chose from.
Astronomical Society of the Pacific offers various student opportunties