I'm sorry, but we are unable to provide contact information or recommendations for any tutors or other services. You might try the CVUSD school district office, or Craig's List.
There are several programs at the Libraries that may help them in their studies, please see:
The Library does offer online Learning and tutoring through our Virtual Library, Resources for K-12, and the Education and Tests page, which includes Gale's Petersons Test Prep, which includes educational materials for the AP tests.