An application for a place on the ballot must be in writing; signed, sworn to by the candidate before a person authorized to administer an oath, and dated; timely filed with the district’s filing authority, Heather J. Mackey or another designated district employee; and contain specified information about the candidate:

• The candidate’s residence address or the address at which the candidate receives mail with a description of the location of the candidate’s residence;
• The candidate’s length of continuous residence in Texas and in the district (and single-member district, if applicable) as of the date the candidate swears to the application;
• If available, a public mailing address and email address at which the candidate receives correspondence relating to the candidate’s campaign;
• The office sought, including any place or other distinguishing number and an indication of whether the office sought is for a full or unexpired term;
• Statements that the candidate is a U.S. citizen; has not been determined by court to be mentally incapacitated; has not been convicted of a felony; is aware of the nepotism law; and swears an oath to support and defend the U.S. and Texas Constitutions and laws.

An individual is eligible to be a candidate for, or elected or appointed to, a Texas school board if the individual:

• is a United States citizen;
• is 18 years of age or older on the first day of the term to be filled at the election or on the date of appointment, as applicable;
• has not been determined by a final judgment of a court exercising probate jurisdiction to be totally mentally incapacitated or partially mentally incapacitated without the right to vote;
• has not been finally convicted of a felony;
• has resided continuously in the state for 12 months and in the territory from which the office is elected for six months immediately preceding the following date:
  * for an independent candidate, the date of the regular filing deadline for a candidate’s application for a place on the ballot;
  * for a write-in candidate, the date of the election at which the candidate’s name is written in; or
  * for an appointee to an office, the date the appointment is made;
• is registered to vote in the territory from which the office is elected on the date described above; and
• satisfies any other eligibility requirements prescribed by law for the office.

Tex. Elec. Code § 141.001; Tex. Educ. Code § 11.066. The Texas Education Code imposes additional requirements:

To be elected to a school board, an individual must be a qualified voter: 18 years of age or older, a U.S citizen, a Texas resident, a registered voter, not determined to be totally or partially mentally incapacitated by an appropriate court, and not finally convicted of a felony. Tex. Educ. Code § 11.061; Tex. Elec. Code § 11.002.

Reference:
Texas Election Code Title 9 Sec. 141.001 
Texas Education Code Sec. 11.061