MILTON -- A Milton Academy official said yesterday the school's decision to expel five male students for receiving oral sex from a 15-year-old sophomore girl was ''excruciating" but necessary to send a strong message to students, as students and parents expressed mixed reactions to the discipline. Three sophomores and two juniors, all members of the boys hockey team, were expelled from the picturesque private campus Friday, after a three-day school investigation found that they requested and received oral sex from a classmate in a school locker room last month, an academy spokeswoman said. ...Two uninvolved students who spoke on the...