This guidance from the Office of Special Ed & Rehabilitative Services addresses the general supervision responsibilities by states and the applicability of IDEA’s child find provisions to children attending public virtual schools. The letter also clarifies the responsibility for providing a free appropriate public education (FAPE) to children with disabilities attending these schools. 

I am not aware of any rules or guidance that TEA has developed.  Many issues arise with virtual schools & students with disabilities – childfind; LRE; provision of related services & specially designed instruction; state assessments, etc. 

For information on this letter,  http://www.ed.gov/news/press-releases/us-education-department-releases-guidance-education-children-disabilities-attending-public-virtual-schools