From the ArcaMax Publishing, Features Newsletter:
http://www.arcamax.com/news/features/s-29397-768994
If your teen is avoiding school, and has anxiety about returning:
Talk to your teenager about why he doesn't want to go to school.
Contact the principal, guidance counselor and school nurse, and make
them aware of the situation.
After you've taken steps to rectify the upsetting circumstances,
insist that your teen return to school immediately.
Severe phobias may require a gradual reentry to school.
After five days of anxiety-related absences from school, it's time to
visit your pediatrician.
Article Source: American Academy of Pediatrics (http://www.aap.org)