Samantha Pellicciotti isn't sure why she's not furious.

She has plenty of reasons to be: the parents who were too drunk and too high to care for her properly, the sexual assault by someone she trusted, the succession of foster homes and string of disappointments.

But the 18-year-old poised to graduate next week as valedictorian of Roxborough High School with a 4.0 GPA and a bouquet of scholarships holds remarkably little rancor. She's moving forward because that's the only path she allows herself to see.

"I'm lucky I'm strong," she said. "I honestly don't know why I'm OK. I just feel like I'm blessed."

Patrick Pellicciotti can barely contain himself.

"I'm the proudest father in the whole world," he said. "She's amazing. She did all this on her own, with no help from me."

In August, Sam will move into a two-year-old dormitory on Temple University's campus, maybe the nicest home she has ever had.

It will be just a few miles - and a world away - from where she began.

Things were tough

Even in Sam's earliest memories, things were tough for her: sleeping on a pool table at a Grays Ferry bar while her parents drank, getting jumped at age 7, bouncing from a rough apartment to a friend's couch to a park bench.

She went to school with dirty clothes because her family had no washer. Her father was jailed for seven years, until she was 13.

"My mom was barely there," Sam said. "I had to go to the bar to find her. I was constantly left alone."

When Sam was 7, her mother attempted suicide, and Sam went to live with relatives in Roxborough, but the situation was not perfect. There were a few stable years, when she lived with her grandmother, and that structure was invaluable.

At 12, Sam was molested by someone she knew. If things were tough before the assault, they became excruciating afterward.

"I would lie in a ball afraid it was going to happen again," she said. "It was eating me up inside. I didn't know who to tell."

She kept quiet for three years, unsure whom to tell. But she found a support system after she started at Roxborough High, and finally confessed to a counselor there.

Her assailant was never charged; that's how Sam wanted it.

"I'm not that coldhearted," she said.

But her admission meant a series of placements in the foster-care system.

One house, in Bucks County, was beautiful.

"My foster mother, she had an in-ground pool, five golden retrievers," Sam said. "But I didn't like the school. I didn't fit in because I was from Philly."

Eventually, she came back to the city, and to Roxborough High, where her support network helped even things out, even if challenges at her foster homes persisted - bedbugs in one place, a family who refused to pay for necessities in another, leaving her to ask friends and trusted adults for supplies.

Though she turned 18 in September, Sam will remain in foster care until she's 21, giving her a place to go on school breaks and summers.

"I'm trying," she said, "to get as much help as I can."

Few know her story

Only a handful of classmates know Sam's story.

Most see what she presents to the world: the sunny young woman who stunned at prom in a lacy red dress and stood out on the softball field and basketball court, the senior class president, the student ambassador, the star student.

"There are people in this school who thought I lived with both of my parents, in a big house, everything always good," she said. "Because I'm always bubbly and happy."

Some teenagers have strong support at home. Sam has Roxborough High.

"God gave me people to help me through, even though my family wasn't present," she said.

Sam focused on school and fixed her sights on college because her teachers told her that was the way to do something great with her life. She is her parents' only child, but she has five half-brothers and half-sisters, all of whom either drink or are in recovery, she said. She will be the first in her family to go to college.

"I'm glad I saw the things I saw," Sam said. "I want to change the cycle."

Dana Jenkins, Roxborough High's principal, admires Sam's wisdom and heart. But she also knows her drive and her intellect - Sam earns A's in Advanced Placement classes and is a strong writer, a nimble thinker.

When steep budget cuts began to squeeze Jenkins and her staff two years ago, Sam asked what she could do to help. She pitched in over the summer; she still works to fill in gaps at the school.

"We look out for Sam," Jenkins said. "We go out of our way to make sure she has the supports she needs to be successful. But we keep high expectations for her."

Eileen DiFranco, Roxborough's school nurse, has met many remarkable students during her long career in Philadelphia schools.

But Sam stands out as "a miracle child," DiFranco said - a kind of Olympic athlete of resilience who never wears her victimhood as a badge of honor.

"Sam is an anomaly. There are other kids that have some of the things that Sam has, and have not been able to make it," DiFranco said. "I have seen her in terrible despair, but she always gets herself back together. It's like everything good came together in her."

Meticulous plan

Inside the worn pink tote bag that goes everywhere with Sam is a black plastic binder encapsulating her future.

Just like Sam, it is impeccably organized: college acceptance letters, scholarship details, and the most important page - a loose-leaf accounting, to the penny, of her expenses at Temple and how she'll cover them.

Her total fees: $29,786. Grants and scholarships cover that and leave about $1,000 for books for the year, plus whatever she can save working at a cellphone store over the summer and on weekends.

College is a fresh start for her, a place to begin working toward the life she can see in her mind's eye.

In 10 years, she hopes to be an FBI agent "with a gun on my side, going to get the child rapist, the kidnapper," she said. "And I want to have a home - not a house, a home. With a husband and two kids, and a cat. I want to give my children the life I never had. I want to create memories, happy ones, because I've had so many sad ones."

DiFranco knows Sam is smart and strong, but she worries about how she'll fare when surrounded by peers who cannot fathom the things Sam has seen.

"I told her that she has to stay in touch with people, she needs to come back when she has a problem," DiFranco said. "Any one of us would be happy to help her."

That's one of Sam's gifts, though - seizing with both hands every bit of help she is offered.

For now, though, there is a graduation to look forward to, a speech to write.

In the audience will be two of Sam's foster mothers, plus her father, who is in recovery, and her mother, who is not, but who pulled herself together to see Sam off to her prom.

Yes, she could be angry, Sam said, but that won't move her forward.

"My grandmother always said, 'Be positive, forgive others,' " Sam said. "I refuse to let myself fall. I've got to get myself right back up."