A city report said that six weeks after the devices were attached to the ankles of 46 students as part of a pilot program in 2007, the students showed up for class 97 percent of the time, the San Antonio Express-News reported Friday.

One of the students, Ana Garcia, said she had previously skipped school so often that she lost track of how many times she was taken to truancy court. But since the device was affixed to her ankle, she has become an A-B student with near perfect attendance, she said.

A San Antonio judge, Precinct 4 Justice of the Peace Linda Penn, said a similar six-month pilot program will be implemented in her city this fall.

"Students and parents must understand that attending school is not optional," Penn said. "It is mandatory. It is the law."