Montel Medley once had difficulty making eye contact and communicating, and was diagnosed with autism. At 17 and with a 4.0 GPA, he was the valedictorian at Surrattsville High School. (Astrid Riecken/For The Washington Post )

Montel Medley’s valedictory speech covered many standard themes: the Class of 2014’s transition from middle school to high school, the impact the graduates’ teachers had on their lives, and the future as many head to college and the beginnings of careers.

Then, Montel delved into something rarely heard from someone with a 4.0 grade-point average, standing before his graduating class, preparing to head to college in a few months. Montel, 17, spoke about his autism.

“Having a disability doesn’t mean you have a disadvantage,” Montel, the valedictorian at Surrattsville High School in Prince George’s County, told the audience. “Sometimes it can be an advantage.”

For Montel, graduating at the top of his class was part of a difficult journey that began with the realization at age 3 that he was nearly non-verbal, then continued through special-education classes in elementary school and ultimately into academic independence and success.

His is not a common path. One in 68 children in the United States has an autism spectrum disorder, one of the fastest-growing developmental disabilities, according to the Centers for Disease Control and Prevention. And those who have autism are less likely to graduate from high school; fewer than 60 percent of students with autism earn a diploma, according to the Autism Society, far lower than the national average of 80 percent as of 2012.

Aisha Clark, the coordinator of the autism program at Surrattsville, said Montel matured during his four years in high school and grew not only to accept his autism, but to embrace it.

“When he came in the ninth grade, he was like the others in the program — they didn’t want to tell anyone they had autism,” Clark said. “By 12th grade, it was the first thing he told people. It was not a setback at all. He would even explain it to people. He’d say, ‘I think differently.’ ”

Clark said Montel’s autism did not affect his course work. He scored high on assessment tests, including earning a 3 (5 is the highest score) on the Advanced Placement Biology exam.

“Academically, he was high-functioning,” Clark said. “Socially, he needed help and support.”

Montel said the autism program taught him to deal with controlling his anger and addressing peer pressure. It even helped him to learn to organize notes and keep track of his assignments, he said.

Roberta Medley, Montel’s mother, said her son was diagnosed with autism when he was 3. She noticed that Montel would rarely look at her when she interacted with him. While other children were talking at his age, Montel’s vocabulary was limited to one word: truck.

She placed him in an infants’ and toddlers’ program run by the county’s Department of Family Services. The school worked with the Medleys, and eventually Montel started uttering more words.

“He began to come around,” Roberta Medley said.

For elementary school, Montel was placed in a separate special-education classroom in Upper Marlboro, outside his boundary area. But soon, his mother said, teachers noticed his solid performance on tests and he was sent to a school closer to his Forrestville home and placed in a mainstream classroom. Until ninth grade, Montel had an aide dedicated to assisting just him. As he moved through high school, an aide helped about four students. By his junior year, Montel was on his own, Clark said.

Before Montel began making the honor roll in elementary school, his mother said she worried about his future.

Montel was born two months premature after his heart rate dropped while Roberta Medley was at a routine doctor’s appointment. He stayed in the hospital for 21 days.

Roberta Medley becomes overwhelmed with emotion when she thinks back on Montel’s past and his accomplishments, including an almost unthinkable 4.0 grade-point average and an acceptance to Towson University.

“I dedicated a great part of my life to see that he flourished,” said Roberta Medley, a single mother, choking back tears as she talked about her only child. “I worked with him a great deal to make him the person that he is now.”

Montel, who enjoys playing video games and creating his own comics, said he looks forward to majoring in applied mathematics at college. This month, Montel and his mother met with a disability staff member to discuss what accommodations the school thinks he might need.

Montel said he plans to follow the same rules that he used at Surrattsville: “I followed directions, I paid attention to my teachers, and I did the work. And I’m planning to do well in college, too.”