A jury heard Amanda Leather, 28, seduced the youngster then tried to cover her tracks by attempting to destroy the boy's phone to get rid of incriminating messages.
Leather was found guilty of one offence of sexual activity with a child after a trial at Leeds Crown Court.
The jury heard Leather and the teenager smoked cannabis as they watched a film at her home before giving him a back massage.
Leather later got into bed with the youngster and they had sex.
The offending came to light after the victim "bragged" to his friends about what had happened and parents contacted police.
Prosecutors said Leather then made attempts to conceal her offending by putting the boy's phone in water and removing the sim card.
Police recovered texts and Facebook messages between Leather in the victim, in which she told him she was "horny" and was having "dirty thoughts" about him.
The jury of eight women and four men found Leather guilty after a three-day trial.
Opening the case at the start of the trial, prosecutor Richard Woolfall told the jury: "It makes no difference if he had the time of his life... or hated every second, the issue is did it happen?
"It is a criminal offence because he was a child by virtue of his age."
Leather, of Coxley Lane, Middlestown, Wakefield, sobbed in the dock after the verdict.
Jailing Leather, Recorder Sophie Drake said: "You have been found guilty by this jury, in my view, on overwhelming evidence.
"You, putting it mildly, messed with his emotions.
"It may be that on his part he wanted to brag about what was happening with you, but at 15 he was not in a position to understand the long term effects that was going to have upon him.
"You encouraged him to take cannabis by buying and smoking it with him.
"What you were trying to do was make him an equal. But he wasn't an equal because he was at all material times a child.
"You used him to satisfy your sexual needs.
"You have made him out to be a liar and have portrayed yourself as the victim in all this. But it is you who has been lying.
"This relatively short-lived behaviour was very much out of character and you have lost that character in the most spectacular way."
After Leather had been sentenced a man walked from the public gallery and said to the jury: "I am Amanda's father and she is only guilty of being a nice person!"
Leather denied having any sexual contact with the boy when she gave evidence at the trial.
She claimed the text messages from her phone had been sent maliciously by the victim to his own phone.
Catherine Silverton, mitigating, said Leather had no previous convictions and continued to deny the offence.
She said: "She has now lost her job, her home and the majority of her friends and colleagues."
The barrister said Leather would struggle to cope with life in custody.
After the case, Det Insp Vanessa Rolfe, of Wakefield Child Safeguarding Team, said: “We welcome the custodial sentence she has received today.
“She fully knew her victim was underage and still pursued a sexual relationship with what was a vulnerable teenager who she plied with alcohol and drugs.
“Safeguarding detectives and the CPS believe this was a clear cut case of sexual grooming and the jury has agreed.
“On her release from prison Leather will now have to sign on the sexual offences register, and I hope this case serves as a warning of the sentences those who carry out these sort of offences can expect to face.”