His release from the hospital comes a day after the alleged gunman turned himself into police.
The suspect, identified as 17-year-old Raisheem Rochwell of the 7400 block of Rugby Street, was charged as an adult.
His attorney, Amato Sanita, declined to comment on the specific circumstances of the shooting, but said Rockwell is a good kid with no prior criminal record.
"I'm saying it's not intentional and we're not admitting any fault on his part," Sanita said.
Two other teens, who were sought for questioning and brought in, have since been cleared.
The shooting happened inside a gymnasium at the Delaware Valley Charter School located at 5201 Old York Road around 3:30 p.m. Friday.
A group of about seven students were apparently hanging out.
An 18-year-old female student was shot in her left arm. Police say the bullet exited her bicep and then struck her boyfriend, the 17-year-old male student, in the shoulder.
Both students were taken to Albert Einstein Medical Center with non-life-threatening injuries.
The female victim was discharged from the hospital earlier in the weekend.
The alleged shooter is charged with aggravated assault, weapons possession and related offenses. He is being held on $500,000 bail.
"He's a good solid kid and you'll see he has no prior record. He stays out of trouble and he's been cooperating with police. Thank you very much," said Sanita.
When asked if it was accidental, he chose another way to describe it.
"Anything that you're hearing out there, this is nothing that involves anything intentional. We can make those comments right now and that's it," said Sanita.
Questions remain about how the gun got into the school in the first place.
Delaware Valley Charter School released a statement indicating that it is working with Philadelphia Police to address security issues. They also say classes will resume on Tuesday as scheduled but with extra security.
Read the full statement below:
First, we would like to thank our families, staff, community, and nation for the concern about the welfare of our students. We are thankful that our students are in good condition and recovering from this unfortunate incident. We will continue to be committed to making sure that the safety of our children and staff is taken seriously inside and outside of school. We are working with the Philadelphia Police Department and Delaware Valley Charter High School's public safety team to ensure that all safety measures are addressed. We will be open and resume school on Tuesday, January 21, 2014 so that our students can continue to receive a quality education. We will have ongoing mental health personnel available to all our students, teachers, and faculty members during this healing process. Security will be heightened to ensure the safety of all of our students and faculty. We would like to thank our parents for their continued support and understanding during this difficult time. We appreciate your partnership so that we can continue to follow our mission making Delaware Valley Charter High School a S.A.F.E. place to learn.
The shooting remains under investigation.
Anyone with information is asked to contact Philadelphia Police at 215-686-TIPS (8477), text a tip to PPD TIP (773847) or through PhillyPolice.com.