The University of South Florida said Thursday it will phase out undergraduate programs in its College of Education and restructure it to become a graduate school. The move, attributed to budget cuts, sent shock waves across local education circles as USF’s College of Education has traditionally been a major training ground for teachers in the region’s K-12 schools. Officials said the change would save $6.8 million over two years. But university officials sought to portray it more as a restructuring to meet changing needs than a budget cut.