Use the "find a lawyer" tool on AVVO to consult an education law attorney. The attorney can deal with the school/district and explain your living arrangements. Have the attorney handle the communications.
We do not have an attorney-client relationship. I am not your lawyer. The statements I have made do not constitute legal advice. Any statements I have made are based upon the very limited facts you have presented, and under the premise that you will consult with a local attorney. This is not an attempt to solicit business. This disclaimer is in addition to any disclaimers that this website has made. I am only licensed in California.
Texas schools take residency issues very seriously because of state funding issues. There are civil and even potential criminal penalties for violating these laws. Contact an education attorney using the Find a Lawyer link on this page. Do not try to handle this one yourself, San Antonio. Get a lawyer to step in and get this straight now, while you are still in control.