The Boston Globe reports that forty-eight superintendents across Massachusetts are calling for cash incentives to attract math and science teachers in an effort to compete with higher-paying private businesses. Currently, teachers are compensated based on their education and experience, generally with across-the-board pay raises. However, in a letter that will be sent to lawmakers and Governor-elect Deval L. Patrick, the superintendents are asking for support to press the issue of incentives with teachers unions, which oppose dramatic changes in pay scales…