The sheriff's office says Lisenby died Monday at a hospital. She was 46.
Authorities say the teacher at Orangefield Junior High School was shot Sunday night.
Investigators spoke with Lisenby's 14-year-old son, who was at home with his mother, and he told them an intruder shot her.
Counselors have been made available to school staff and students in the community of 700, located about 100 miles northeast of Houston.