SWAMPSCOTT – High school science teacher Lytania Mackey will become the school’s new dean/curriculum leader, Superintendent Lynne Celli recently announced.”She’s well aware of the challenges but is ready to rise to the occasion,” Celli told the School Committee recently.Celli proposed the new, full-time position – with responsibilities divided evenly between both dean and curriculum-development roles in May – to help the high school complete steps necessary for retaining its accreditation by the New England Association of Schools and Colleges.In April, High School Principal Layne Millington reported that an evaluation by the association sanctioned the high school for not meeting three out of the seven evaluation standards. The association’s report cited the lack of a complete written curriculum for the high school as a major issue.Celli said in May that the new position would enable the high school and district to address this problem.Celli expressed confidence that Mackey could do that job, noting that she had led the self-study component of the evaluation.