mary todd lowrance , teacher at moises e molina high school , turned herself into dallas independent school district police on thursday morning .
dallas isd police said she had been in a relationship with student , who is older than 17 years old , for a couple of months .
she confided in coworker who alerted authorities and police eventually got arrest warrant .
lowrance was booked into county jail on $ 5,000 bond and has been released from the dallas county jail , according to county records .
she has been on leave for several weeks while investigators worked on the case , police said .