"I also want you to write a 300-word essay on why you did this and give a written apology to your grandmother," Boone said.
Assistant Washington County State's Attorney Gina Cirincion said she wasn't impressed by the brief show of remorse in court Wednesday.
"She has bragged that she will beat this charge," Cirincion told the judge.
The grandmother said she wants the girl to receive intensive counseling.
The incidents came to light July 10 when the loss-prevention staff at the J.C. Penney department store observed the teen charging merchandise at one register and trying to return it for cash at another, Cirincion said.
She made seven purchases worth $495.14 and got refunds on four purchases totaling $190.04, Cirincion said.
Subsequent purchases exceeding $200 at Bon Ton turned up, Cirincion said.
Restitution has been paid in those cases, according to defense attorney Jay Beasley. All but $900 on gas cards has been repaid, he said.
Boone ordered a post-disposition report on the girl, noting that if anything "glaring" shows up, the case can be returned to court.
School reports noted she missed 37 days in her senior year, withdrew, received her GED and is now enrolled at Hagerstown Junior College.
An addictions counselor told Boone the girl tested positive for drugs when initially screened but has been negative ever since.
Her mother and stepfather said she has been doing well in college and has kept her curfew since it was set in July.
The grandmother said she has had no contact with the girl since July. She said the credit cards were taken from her purse while the girl was at her home.