Astronomy

• Andrew Fraknoi's Astronomy Resources
• Bay Area Astronomy Connection
• Robert Ferguson Observatory - near Santa Rosa
• NASA AMES Research Center: Education | Visit
• Sky and Telescope Magazine
• The Planetary Society
• UC Berkeley Astronomy Dept.

Biology

• Harvard Biological Sciences Multimedia Lab presents: Biovisions: The Inner Life of the Cell
• Dissect a frog online
• The Virtual Cell

Chemistry

• The Periodic Table (interactive)

Summer Programs for High School students in California and throughout the U.S.

• College of Marin Summer Courses - 2010 summer courses available in Astronomy, Biology, Chemistry and Math
• Santa Rosa Junior College Summer Courses
• Stanford EPGY Summer programs - Science & Engineering | Computer Science | Mathematics
• National Student Leadership Conference summer programs in: Engineering | Medicine & Healthcare | Forensic Science
• UCLA Summer Institutes - Marine Biology | Stem Cell Science | Future Physicians |
• USC Summer Program - Discover Engineering | The Brain & Neuroscience |
• COSMOS: California State Summer School for Mathematics and Science (2010 Closed - Application for 2011 will open February 1, 2011)
• UCSF Biomedical and Health Sciences Internship for Underrepresented High School Students - (2010 Closed - Applications for 2011 available in November 2010)
• Stanford School of Medicine Summer Residential Program -"Promoting the representation of ethnic minority and low-income groups in the health professions." (2010 Closed - Applications for 2011 available later in the year) More info.
• The Summer Science Program at CalTech - Gifted high school students complete a challenging, hands-on research project in celestial mechanics. (2010 Closed - Applications for 2011 available later in the year)
• Stanford University Mathematics Camp - (2010 Closed - Applications for 2011 available later in the year)
• NIH (National INstitutes of Health) Summer Internship program in Biomedical Research (2010 Closed - Applications for 2011 available in November 2010)
• Buck Institute Summer Scholars program (on hiatus for 2010)
  

Extracurricular

• Nano-High at Lawrence Berkeley National Laboratory: 2009-2010 flyer here
• Bay Area Science - Portal for all things science in the bay area, especially those education-related.
• Science Cafes - Find other free Bay Area science seminars.
• Science at Cal: UC-Berkeley events, activities, news, research and the East Bay Science Cafe.
• Physics for Future Presidents