The panel deliberated about 90 minutes Wednesday before finding Danielle Black guilty of solicitation of first-degree murder.
She faces up to life imprisonment at her sentencing, which has not been scheduled.
Danielle's father, 47-year-old Billy Lee Black, was stabbed to death outside the family's Hagerstown home on Halloween. The man charged with killing him is not the same friend Danielle was convicted of approaching on a school bus a few days before the slaying.
In closing arguments on Wednesday, the prosecutor portrayed Danielle Black as a girl obsessed with her father's death and her twisted hatred of him.
But the defense said Danielle, and the boy on a school bus she allegedly approached, were just teenagers saying things they didn't mean.
The state rested Wednesday after presenting its star witnesses - two teenagers who were little help in proving that Danielle Black asked a friend on a school bus to kill her father.
Defense attorneys said they would rest after an afternoon recess. Black declined to testify.
The 18-year-old who allegedly received the request testified that Black asked him to "take care of" her father, not kill him. A 14-year-old prosecution witness testified that she overheard Black discuss a murder plan, but she said the conversation happened Oct. 31, at least five hours after Billy Lee Black was killed.
Her testimony contradicted the timeline she gave to police.