Newcastle Local Court magistrate Robert Stone said Jackie Hays, 51, was remorseful, unlikely to reoffend and would continue psychiatric treatment in the community which was not available in prison.

Mr Stone placed Hays - who sobbed in court while being sentenced - on a 12-month good behaviour bond after accepting she was "immensely sorry" for the inappropriate behaviour which had been out of character.

The magistrate said Hays, who's been diagnosed with a borderline personality disorder, was disappointed with herself and had learned from her mistakes.

Hays pleaded guilty to grooming the 15-year-old student for sex in 2015 after becoming infatuated with him. She sent him numerous explicit text messages. The 51-year-old turned to the boy's mother on Wednesday and said "sorry darling" before leaving court.

Hays had blamed the weight loss drug Duromine for causing her sex drive to increase and impair her judgement, but Mr Stone found the drug had had no significant impact on her behaviour. 

Legal Aid lawyer Gillian Jewison had argued Hays started taking Duromine four months before she began targeting the teenager. While there was no medical evidence linking the drug to Hays' offending, Ms Jewison said Hays’ friends noticed she seemed to be acting bizarrely.

When Hays was interviewed by detectives she described the text messages sent back and forth to the boy as "filth".

Hays, who was 47 at the time, was willing to have sex with the teenager who attended the same Hunter Valley school where she and the boy's mother worked. But she claimed she wanted to wait until he turned 16.

Mr Stone said the mother of three had been in an unhappy marriage and her emotional needs were unmet when she began sexting the boy. 

"She knew she was doing the wrong thing ... she knew it was very inappropriate," the magistrate said.

"Children are to be protected from any sexual conduct - even if they are willing participants."

Prosecutors had called for Hays to be jailed. She would have faced a maximum of 10 years in jail if the case had been heard in the District Court, but prosecutors agreed to have the matter dealt with in the Local Court where the maximum penalty was two years. 

Hays was charged with five offences alleging she had been sending explicit text messages and phoning two students, but four of the charges were dropped after she agreed to plead guilty to one count.

While you’re with us, did you know The Herald is now offering breaking news alerts, daily email newsletters and more? Keep up-to-date with all the local news - sign up here.  

AAP