89.1035(a)
19 Texas Administrative Code § 89.1035. Age Ranges for Student Eligibility.

(a)  Pursuant to state and federal law, services provided in accordance with this subchapter must be available to all eligible students ages 3-21. Services will be made available to eligible students on their third birthday. Graduation with a regular high school diploma pursuant to §89.1070 (b)(1), (b)(2)(D), (g)(1), (g)(2), (g)(3), or (g)(4)(D) of this title (relating to Graduation Requirements) terminates a student's eligibility to receive services in accordance with this subchapter. An eligible student receiving special education services who is 21 years of age on September 1 of a school year will be eligible for services through the end of that school year or until graduation with a regular high school diploma pursuant to §89.1070 (b)(1), (b)(2)(D), (g)(1), (g)(2), (g)(3), or (g)(4)(D) of this title, whichever comes first. 
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Last Amended:  December 2, 2015, 40 TexReg 8642
Entered:  December 8, 2015