ABC

A former Texas high school English teacher and mother of three is on trial, accused of having sex with five male students.

The evidence against Brittni Colleps, 28, includes cell phone video that allegedly shows group sex between her and four students at her home. Prosecutors say it happened while her children and husband, who is an Army specialist stationed out-of-state, were away. The graphic video was shown to the jury this week.

"She [Colleps] said that she craved, that I had something that she wanted," one of the students involved testified.

Police say the alleged incident took place at her Arlington, Texas home in April and May of 2011, according to ABC News affiliate WFAA. Since all of the students were 18 at the time of the alleged incident, Colleps is not facing statutory rape charges. Instead, she has been hit with five counts of having an improper relationship with a student.

One student told WFAA that one of the teenage boys was bragging about the alleged incident and another student put the claim in her diary. A teacher at the school found the diary in a classroom and that's when the school notified police.

Some of the students, who were attending Kennendale High School, took the stand on Tuesday but were not identified because of their ages and the nature of the crime, according to WFAA.

One of those students said his relationship began with an innocent text message. "Hey… It's Coach Colleps. Do you know what time the baseball game starts?"

Soon after that the student says that he and Colleps were exchanging almost 100 texts a day. The prosecutor says that the relationship progressed into explicit text messages and then an agreement to meet for sex.

One of the young men she is accused of sleeping with has publicly stated that she didn't commit a crime.

Colleps' husband, Christopher, is sticking by his wife despite the accusations.

"If you know Brittni, you know she's an empathetic loving, loyal person. Brittni is a loving mother and continuously puts the needs of our children above her own," Christopher Colleps said before the trial began.

Brittni Colleps was suspended by the school district and her contract was not renewed this year, so she is out of work during the trial.

"She's terrified … she has no idea whether she is going to prison next week or whether she will be home," her attorney said.

If Colleps is convicted, she could spend 20 years in prison.