Hey, I can't afford private HS's either, but most of the good boarding schools have lots of money available for Financial Aid, which is awarded based on need. Maybe if you told your parents you thought you could get a better education, and gain a greater love of learning, blahblah, etc, etc.
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Lil' Angel 
Sword Saint and Enchantress of the HADB Clan
The Lady Lioness of Castle Kerhelm
Waitress at Cloudy's Cafe and the Promised Land
Official Restrainer of Table Dancers
PeaceKeeping Force, Intelligence Division