A former Plano Senior High School algebra teacher was sentenced to probation Thursday after an inappropriate relationship with a student that included beer pong, nude photos and numerous sexual encounters.

Alaina Ferguson, shown here after being arrested Nov. 30, 2016, pleaded guilty to having an improper relationship with a student. (Courtesy Collin County Detention Center)

Alaina Ferguson, 25, pleaded guilty to charges of an improper relationship between a teacher and a student and indecency with a child by exposure. She received 10 years' deferred adjudication probation and was fined $800.

She was also sentenced to 120 days in Collin County jail, which will be served two weeks a year over several years. Ferguson must also complete 150 hours of community service and register as a sex offender for 10 years.

Ferguson's attorney declined to comment Thursday.

Court documents say the relationship began after one of Ferguson's 16-year-old students included his Snapchat user name on a test in the fall of 2016. The two later met up and had sex on a park bench in Lewisville, the affidavit stated. They also had sex at her then-fiance's apartment in McKinney and in the back of his truck, documents stated.

Ferguson reportedly told the teen "she knew it was not the right thing to do, but it felt right at the time."

The two also exchanged nude photos over the phone. Ferguson gave the teen alcohol during their two-month relationship, according to the investigation by McKinney police.

Ferguson had been hired in Plano ISD in August 2016 and resigned two months later.