Jack Harrington & John F. Fitzgerald of Atlantic Associates, Inc. with The Home for Little Wanderers' President and CEO Joan Wallace-Benjamin. When he was a boy, Jack Harrington played baseball in a vacant lot on Alleghany Street in Roxbury with kids from the neighborhood. Now a man of 46 and the president of a West Roxbury business, Harrington is returning to that street, overseeing the refurbishment of the Mission Hill Convent across from the still-vacant lot. The convent will house eight children with behavioral difficulties who are waiting to be adopted, placed in foster care, or returned home. "This is the result of a lot of good people coming together," Harrington said yesterday, deflecting prais from several associates touring the convent yesterday afternoon. "The people who take care of these children are the amazing ones". Harrington, with the help of volunteers, a local news channel doing an "extreme makeover" and businesses donating items such as kitchen appliances, furniture, and paint, hopes to have the convent ready before Chrismas, so the children can celebrate the holiday in new digs. "Here you have a man that has a full-time job, but he's giving a lot of his time and money to seeing this whole thing through," said Edie Janas, 37, the program director for the Spring Park Place, the Jamaica Plain home where the children are now housed. When Harrington saw Spring Park Place several years ago, he was dismayed with the lack of space and the overall condition of the house. Knowing that the Home for Little Wanderers, which operates the house, was looking for new accomodations, Harrington started searching. After failed attempts in Hyde Park and Dorchester, he and his business partner, John Fitzgerald, found the convent. The convent will be temporary housing. Harrington is also spearheading the building of a house with a more residential feel to it.