Rhonda Eisenberg, 44, was booked into the Weld County Jail under two felony complaints of patterns of sexual assault. Greeley police received an online tip regarding the alleged relationship.
Police say the teen is from Mexico and was attending Eisenberg's classes at North Ridge High School. The Weld County teacher was also the victim's legal guardian at the time of the alleged assaults.
Investigators say Eisenberg admitted to having sex with the teen 20 to 30 times between 2010 and 2011.
Authorities say Eisenberg and the teen had a baby together, who was born February of last year.
The Greeley Tribune is reporting that Eisenberg is on paid administrative leave from Greeley-Evans School District 6.
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