Perry's executive order is online here:
http://www.governor.state.tx.us/divisions/press/exorders/rp65
The last clause requires parents wishing to exempt their daughters to fill out a "conscientious objection affidavit" with the state government.
What a convenient way to get a list on non-compliers for the government to track. Filled out by themselves, no less. It saves the government the time and trouble of searching out the rabble rousers themselves.