Because a juror had a prior commitment, they met for only two hours. Jurors will resume a full day of deliberations on Tuesday.
They will be deciding the fate of 17-year-old Brandon McInerney, who is accused of murdering Larry King, a gay classmate, at E.O. Green Junior High School.
Prosecutors say McInerney, who was 14 at the time of the shooting, targeted the 15-year-old King in a homophobic, white-supremacist rage.
The defense says King provoked the shooting with sexual advances toward McInerney.
McInerney has pleaded not guilty to one count each of murder and a hate crime. If convicted, he faces more than 50 years in prison. Jurors also can consider a conviction of voluntary manslaughter, which carries a maximum 21-year term.
The Associated Press contributed to this report.