Supporting Success for High Need Students Act of 2003

Supporting Success for High Need Students Act of 2003 - Amends the Individuals with Disabilities Education Act (IDEA) to direct the Secretary of Education to make grants to State educational agencies (SEAs) to establish high-cost funds from which local educational agencies (LEAs) are paid a portion of: (1) the costs of providing a free appropriate public education to high-need children; and (2) other high costs associated with educating children with disabilities under IDEA part B.

Allocates such grants to States using the IDEA part B allotment formula; and authorizes appropriations for such targeted grants. Permits LEAs to apply for disbursements from the SEA's high-cost fund to offset 75 percent of that portion of a high-need student's education that costs more than four times the average per pupil expenditure (in the Nation or State, whichever is lower). Allows disbursements to cover education and related services included in an appropriately formulated Individualized Education Plan. Prohibits use of such disbursements to pay: (1) costs otherwise reimbursable as medical assistance under the State Medicaid program; (2) inappropriate or unnecessary excess costs disallowed by the SEA; or (2) legal, court, or other costs associated with a cause of action brought to ensure a free appropriate public education for a high-need child.