In New York City's funny math, you get only one teacher for the price of two. The Department of Education pays about 1,500 teachers for time they spend on union activities -- and pays other teachers to replace them in the classroom. It's a sweetheart deal that costs taxpayers an extra $9 million a year to pay fill-ins for instructors who are sprung -- at full pay -- to carry out responsibilities for the United Federation of Teachers. With Mayor Bloomberg calling for thousands of teacher layoffs to balance the 2012 budget, critics say it's time to halt the extravagant benefit. 1,500 Teachers Paid to Do Union Business While Missing Class - FoxNews.com TAXPAYERS UNITE.