BOSTON —

A former college entrance exam administrator has agreed to plead guilty in the college admissions bribery scheme that has ensnared wealthy parents across the U.S., federal prosecutors said Wednesday.

Niki Williams, a former employee of the Houston Independent School District, will plead guilty to accepting bribes to help rig students' test scores, prosecutors said.

Williams, 46, was one of 50 people arrested last year in the scheme, in which authorities say undeserving kids were admitted to top universities with bogus athletic credentials or fake test scores.

Prosecutors say Williams, who administered the college entrance exams at the public high school where she worked, took bribes from the admissions consultant at the center of the scheme, Rick Singer, in exchange for allowing someone to take exams in place of the children of Singer's clients or correct their answers.

Williams will plead guilty to one count of conspiracy to commit wire fraud and mail fraud and honest services wire fraud and mail fraud, officials said.

An email seeking comment was sent to her attorney.

Others who've pleaded guilty in the case dubbed "Operation Varsity Blues" include "Full House" actor Lori Loughlin and her fashion designer husband, Mossimo Giannulli.

The famous couple is scheduled to be sentenced next week after admitting to paying half a million dollars to get their two daughters into the University of Southern California as crew recruits even though neither girl is a rower.

Loughlin's plea deal calls for her to serve two months in prison while Giannulli's calls for him to serve five months.