Notwithstanding any other provision of this chapter, no handicapped patient under twenty-one years of age or the estate or the parent of such patient may be charged for educational or related services provided at the state hospital. However, the department has prior claim on all benefits accruing to such patients for medical and medically related services under entitlement from the federal government, medical or hospital insurance contracts, workforce safety and insurance, or medical care and disability provisions of programs administered by the department. For the purposes of this section, “related services” means transportation and such developmental, corrective, and other supportive services, as determined by the department of public instruction, as are required to assist a handicapped patient to benefit from special education. The cost of related services, other than medical and medically related services, must be paid by the state hospital, the school district of residence of the handicapped child, and other appropriate state agencies and political subdivisions of this state. The department of public instruction, the department, the school district of residence, and other appropriate state agencies and political subdivisions, as determined by the department of public instruction, shall determine and agree to that portion of related services, other than medical and medically related services, for which each such agency and political subdivision shall be liable. The department of public instruction may adopt rules necessary to implement this section.