As federal aid for students uprooted by Hurricanes Katrina and Rita begins making its way to cash-strapped school districts, many educators are worried that the money Congress allocated will fall well short of their costs. Since the hurricanes damaged hundreds of schools in the Gulf Coast region and initially dispersed nearly 375,000 students, districts around the country have tapped their own coffers to pay for extra teachers, textbooks, school supplies, tutors, and other resources for evacuees. Many districts had expected to receive $6,000 this year for each general education student and $7,500 for each student in special education, the maximum allowed in the federal law that establishes what is called the "impact aid" reimbursement program. Some district leaders fear that the actual amount they receive under the $645 million program will be lower, possibly two-thirds of what they had anticipated per student.