State legislators now say it will cost 900 million dollars per year to give Arkansas public school students an adequate education. The previous figure was 709 million dollars. But the estimate was adjusted upward to account for contributions to teacher retirement and what some school districts provide above the mandatory 25 mills set by the state. The state cant ask districts with higher millages to subsidize other districts. Thus, the 146 million dollars raised by districts with higher millages cant be used toward statewide education improvements. If the state is to raise the 900 million dollars, it would have to come from a broad-based tax, like a sales or income tax. Earlier Monday, the members of the legislative committee discussed whether or not Arkansas should cover the cost of preschool for poor children. The special committee is meeting to determine the per-student cost of providing Arkansas public school children an adequate education.