The content of some of the messages shared between the pair was sexually explicit, police allege.
Laidlaw appeared briefly in court this week where police claimed she told the student she had feelings for her and asked her to sneak out of her apartment to meet up.
The teen, who cannot be named, claimed that Laidlaw touched her inappropriately on two occasions in August and kissed her in the back seat of her car, according to police.
She also alleged that Laidlaw asked her to send sexually explicit messages back, in response to messages she had been sent by her teacher, but the teen refused.
The Chronicle reports the alleged relationship "came to light" when the girl's father found messages between her and Laidlaw on his daughter's phone.
Laidlaw has been suspended from her teaching job while the charges are pending and released on bail.
The Spring Branch District where Laidlaw was teaching released a statement declaring "outrage" at the alleged conduct of one of its staff members.
"The safety of every student is our very highest priority, and having a strong moral compass is a key district core value," the district said in the statement.
"We will never tolerate inappropriate actions on the part of any district employee who endangers or harms our students. These allegations, if true, are a complete breach of the trust our children, our community, and we place in our educators."
Counsellors have been asked to attend the school to talk with students if required.