FRESNO, Calif. -- After spending 25 years in prison, even Arnold Trevino is shocked by how far he's come."It's really an experience that I don't even feel like it really happened," Trevino said while walking the Fresno State University campus. He graduated from the school with a master's degree as a Dean's Medalist earlier this year, but his success came after decades of trials."By the time I was 21 I was a real knucklehead, doing heroin, cocaine... I mean, you name it, I was doing it. And I eventually went to a party and I got into a fight. I lost the fight," Trevino said. "I was really, really embarrassed as a result of it. And I came back and I stabbed the guy. You know, he didn't have it coming. Not to that extent. He ended up dying and I was sentenced to 16 years to life for second-degree murder. And I spent the next 25 years in prison."During his time behind bars, Trevino participated in educational programs and eventually earned his high school diploma and an A.A. degree in liberal arts. He spent seven of his 25 years at Avenal State Prison and was released in 2011."What education did for me, I mean, seeing the world through an academic lens change the whole perspective," Trevino said. He decided to go back to school and earned another A.A. from Porterville College. He then transferred to Fresno State in 2015, earning a bachelor's degree in 2017 and his master's degree in 2019. He was also named a Dean's Medalist at graduation.Trevino is out to prove that change is possible, even for people who are locked up. He now spends his time helping lead the Insight Garden Program at Avenal State Prison. The program teaches inmates about nature and ecosystems while rehabilitating them in the process."While the inmates are digging in the soil, learning about the particles that make up the soil, they're also metaphorically digging within their soul," said Dee Lovette, community resources manager at the prison. "And they're learning about the unique qualities that make them who they are.""For him to be incarcerated, you can tell the class focused on what he had to say. And It was awesome," said Esteban Rocha, an inmate at Avenal and a participant in the program. "Because, you know, he's been through it, he related to us, he knows what it's like... And I didn't know there was so many doors for us that can be open. And he brought that to our attention."When he's not at Avenal, Trevino can likely be seen at the Fresno State campus volunteering his time with Project Rebound, a program focused on aiding former inmates through college."What we do is assist with the application for the university," said Emma Hughes, the chair of the criminology department at Fresno State. "And then we just give general advice about what life is like and then if students are accepted, we create a community of support and mentorship.""About 95% of the people currently incarcerated will come back into the community," she said. "So something we have to ask ourselves is: what do we want to have happened while they were incarcerated?""It's also an understanding that we are actually saving money," she said. "A study done by RAND in 2013 showed that for every dollar spent on education programs in prisons you save about 5 dollars over the next few years because of the fact that you're reducing re-incarceration."Trevino hopes his story encourages other inmates and shows that change is possible."Just to show them we can do it. I was there, in your shoes and I want you to be here in my shoes," he said. "There's nothing stopping us but us."