Physical therapist Lauren Fery spots student Kamille Davis as she climbs up the playground ladder at St. Coletta. (Calla Kessler/The Washington Post)

With a mailbag slung across his small frame and a wide-brim hat perched atop his head, Mason Wade stepped up to the catwalk. Clasping his aide’s hand for support, he sashayed across the gym, a sprawling red carpet under his feet.

For the 6-year-old dressed as a mail carrier, his favorite community helper, the end-of-year fashion show at St. Coletta Special Education Public Charter School in Southeast Washington was a chance to strut his stuff. For the school-based therapists looking on, it was a moment years in the making.

Mason, who has a developmental delay, used a wheelchair when he started at St. Coletta in 2015. Hundreds of physical therapy sessions and oodles of enthusiasm later, Mason is walking, able to traverse the school’s black-and-white-tiled hallway with the support of an adult.

Mason Wade used to rely on a wheelchair, but he can now walk with minimal support. (Calla Kessler/The Washington Post)

Physical therapist Keith Albarillo works with Mason, 6, at St. Coletta school. (Calla Kessler/The Washington Post)

At St. Coletta, where all students have special needs, tiny pieces of progress can add up to life-changing trajectories. The school relies on funding from Medicaid to employ a cadre of therapists. But with each twist in the health-care debate on Capitol Hill, staff members wonder whether their Medicaid dollars could be at risk.

Pride for student achievement is shadowed by anxiety over the unknown.

“We would not rest easy if we knew we couldn’t provide the appropriate services for our kids,” said Loni Licuanan, who directs the school’s therapeutic services.

The federal government allows public schools to receive Medicaid reimbursement for school-based health services required through students’ special education plans. Although federal law mandates that schools provide these services, Congress has never authorized the amount of funding it pledged when the law was passed decades ago. To make up that budget gap, schools have turned to Medicaid.

The District, which expanded Medicaid coverage in 2010 under the Affordable Care Act, received more than $40 million in Medicaid reimbursements for ­special-education services during the last fiscal year, according to the Office of the State Superintendent.

Cuts to Medicaid would affect schools across the District, but St. Coletta would be especially hard-hit. Each of the school’s 250 students is intellectually disabled, and most require multiple types of therapy.

During fiscal 2016, St. Coletta provided more than $1 million in special-education services to Medicaid-eligible students. The school was reimbursed for 70 percent of the cost through Medicaid, which helps pay the salaries and benefits of 35 service providers, including physical therapists, occupational therapists and speech-language pathologists.

Overall, Medicaid reimbursements account for only 5 percent of St. Coletta’s annual budget, but the school says those funds — more than $750,000 annually — make it possible to provide services not available at other D.C. public schools.

In addition to weekly one-on-one sessions, St. Coletta students have therapy as part of their daily routines. Bathroom breaks are used as skill-building opportunities, from support walking across the hall to guidance in using a toilet independently. At lunchtime, where feeding and swallowing can be arduous for some students, therapists assist.

Antoinette Davis of Southwest Washington said school-based therapy has given her daughter, Kamille, the confidence to make new friends and to climb the spiral stairs in the family’s duplex.

Speech therapist Sherelle Smith works with Kamille Davis at St. Coletta. (Calla Kessler/The Washington Post)

Kamille, 6, has Smith-Magenis syndrome, a rare genetic disorder that can cause delayed speech. As a toddler, she was nonverbal. Unable to express herself, she resorted to self-harm, scratching her arms and banging her head, Davis said.

“She would get mad and frustrated because we didn’t know what she wanted,” she said.

Since enrolling at St. Coletta two years ago, Kamille has learned to use a specialized tablet to communicate her needs and to show what she’s learned.

“She knows her colors, the alphabet, how to spell her name,” Davis said. “I can see the difference in her.”

Located across from the D.C. Armory, St. Coletta educates students until they turn 22. Because of the severity of students’ disabilities, there are no grade levels. Students are separated by age.

Brandon Walker has learned to use an eye-gate system to communicate. (Calla Kessler/The Washington Post)

Brandon Walker, 20, is a member of the school’s oldest group. A student at the school for more than a decade, he is unable to walk or speak. It took a team of therapists years to find a communication system that worked for him, said Katherine Short, the school’s therapy coordinator.

Walker uses eye-tracking technology to communicate. A camera inside a tablet-like device mounted to his wheelchair monitors his eye movements back and forth, as one might a cursor moving across a computer screen. When his eyes dwell on an image for one-sixth of a second, the machine says the chosen word for him.

Using the device, Walker can tell his teacher when he’s hungry, tired or in the mood to listen to his favorite jazz music. And, for the first time, he can engage socially.

The technology, purchased by his family through Medicaid, “gives him access to his world, access he never had before,” said Short, a speech language pathologist.

According to a report from the Office of the D.C. Auditor, the District would lose $563 million in federal funds for Medicaid in the first year and up to $1 billion annually by 2028 if Congress were to repeal the Affordable Care Act.

If the federal government reduces its share of Medicaid spending, schools might have to compete with other medical providers, including hospitals and nursing homes, for limited resources, said John Hill, executive director for the National Alliance for Medicaid in Education.

“There’s going be losers, and it will be up to the states to decide who those losers are going to be,” he said.

Sharon Raimo is the chief executive of St. Coletta. (Calla Kessler/The Washington Post)

For Sharon Raimo, St. Coletta’s chief executive, that prospect can be maddening.

Raimo, who helped found the school in 2006, said any threat to her students’ safety net is worrisome. Medicaid cuts, in particular, would be shortsighted, she said.

“When these kids attain these goals, it makes them easier to take care of at home, rather than being placed outside of the home, which is much more expensive,” she said.

St. Coletta already fundraises for many of its needs and would seek additional support from donors if necessary.

“These are the people who make my heart beat faster,” she said. “Everybody here who does this work, we do it because we care about them and we really think they have potential.”