The former Woodrow Wilson school on Croftland Avenue, now Dorchester Academy. Photo courtesy Dorchester Atheneum

A plan approved by the Boston School Committee in December will dramatically increase the number of available seats at Dorchester Avenue’s coveted William Henderson Inclusion School beginning this fall.

A key aspect of the plan will be the gradual relocation over the next five years of the school’s upper grades – along with students from the Harbor Pilot Middle School – to the former Woodrow Wilson campus on Croftland Avenue off Gallivan Boulevard near Codman Hill.

The initiative, crafted by the schools’ principals with input from families and school officials, will make the Henderson the only fully inclusive K-12 public school in the state with room for as many as 1,000 students.

The Henderson, formerly known as the O’Hearn School, is now a K-to-5 school that educates students with disabilities in the same classrooms as their non-disabled peers. It is affiliated with the Harbor School on Charles Street, which accommodates students in grades 6-10, including many former students of the Henderson, which serves as a “feeder” school for Harbor. Under the plan, the existing Henderson School will eventually serve students in grades K-0 through grade 2 while the upper grades will be relocated to the Wilson campus in phases beginning next September. Fourth and fifth grade students from the Henderson and sixth through tenth graders from the Harbor will begin attending classes at what will be known as the Henderson’s Upper School. Students at Dorchester Academy, which currently occupies the Wilson building, will be relocated to the Harbor School’s present location at 11 Charles St. in Fields Corner.

Trish Lampron, principal of the Henderson School, and Nadia Cyprien, principal of the Harbor Pilot Middle School, briefed neighbors about the plan at a meeting of the St. Mark’s Area Civic Association last week. Lampron said the merger is the right solution to accommodate the students who are on the Henderson School’s waiting list each year. The Henderson now has 10 classrooms and an enrollment of 250 students. “This past September there were 750 kids on the waiting list,” Lampron said. “I think parents need choices and the Henderson is a choice for many.”

The merger will double the amount of students at the Henderson, said Lampron, and will serve 1,000 students when the five-year rollout is completed. In the past, administrators from both schools tried to create a pathway into the Harbor School for students from the Henderson School, but without much success, in part because there is not enough room at the Harbor’s facility for grades 11 and 12. The imminent merger will also allow students to stay at the same school until they graduate from twelfth grade or, for those with moderate or severe disabilities, until age 22 if they need more time to matriculate.

Dianne Lescinkas, a parent who has one daughter in the 10th grade at the Harbor and another who is a fourth grader at the Henderson, said that she and others in the school community are excited by the proposal’s progress. Lescinkas has served as the co-chairperson of the Harbor School’s governing board for five years and advocated for approval of the plan by the School Committee.

For parents who did not have choices before, it’s such a big milestone to know that if you have a child who has a disability, they can be included with typical kids, said Lescinkas. “This will be the first fully inclusive high school to include kids considered to have moderate to severe disabilities. It will allow these kids to be included in the classroom, and it’s really a big deal.”

Lescinkas said that she and other parents feel it makes sense to expand into the Wilson campus to give older and younger students their own learning spaces. “I do feel like the building is definitely appropriate. There’s an incredible life skill room and full kitchen. There’s space in back for universally accessible playground and, hopefully, with grant-writing, an outdoor classroom. And there’s a beautiful auditorium.”

At last Tuesday’s meeting. Cyprien said her students at the Harbor are prepared for the changes, adding, “we’ve started educating [them] on how to be in an inclusive environment.” Parents of fourth and fifth grade students at the Henderson were invited to a meeting this past Tuesday to review plans for the transition. A site visit to the Wilson campus for parents is scheduled for next Tuesday, Feb. 11.

The merger will guarantee that students from the Henderson School aren’t “educated differently than the foundation education they’ve gotten,” said Lampron. “Our scores on the state tests are the highest in the district. We really believe that’s because we educate all students together,” she said.

As it’s implemented, the plan will lengthen K-0 classes from half-day to full-day, add classrooms to grades one and below, and reduce the amount of classrooms for grades six through nine by one while adding grades 11 and 12. “We’re decreasing our classrooms, but not the number of students to each classroom,” Cyprien said.

The new Henderson K12 Inclusion School will have three principals: Cyprien, Lampron, and Isabel DePina, the headmaster of the Harbor School. In 2009, the school was re-named to honor the longtime principal of the O’Hearn School, Dr. William W. Henderson, upon his retirement.