Improved Adoption Incentives and Relative Guardianship Support Act of 2008

Improved Adoption Incentives and Relative Guardianship Support Act of 2008 - Title I: Extension and Improvement of Adoption Incentives - (Sec. 101) Amends part E (Foster Care and Adoption Assistance) of title IV of the Social Security Act (SSA) to: (1) extend the adoption incentives program through FY2012; (2) increase the incentive payment to a state, according to a specified formula, for exceeding the highest ever foster child adoption rate; and (3) increase incentive payments for special needs adoptions and older child adoptions.

(Sec. 102) Revises requirements for the adoption assistance program with respect to the adoption of children with special needs.

Title II: Support for Relative Guardianships - (Sec. 201) Gives states the option to provide for relative guardianship assistance payments for children. Prescribes requirements for such payments.

Requires the use of unawarded adoption incentive funds to make relative guardianship incentive payments.

Makes children who exit foster care for relative guardianship or adoption after age 16 eligible for independent living services and education and training vouchers under the John H. Chafee Foster Care Independence Program.

Requires a state plan for foster care and adoption assistance to provide that, within 30 days after removal of a child from the parent's or parents' custody, the state shall exercise due diligence to identify and notify all the child's adult relatives of the removal, and: (1) explain the relative's options to participate in the child's care and placement; (2) describe the requirements to become a foster family home, and the additional services and supports available for children placed in such a home; and (3) explain the availability, if any, of kinship guardianship assistance payments.

Provides for a penalty in connection with the state's Temporary Assistance for Needy Families grant for noncompliance with such notice requirements.

Requires the state to inform any individual who is adopting, or whom the state is made aware is considering adopting, a child in foster care under state responsibility of the individual's potential eligibility for a federal tax credit.

Sets forth case plan requirements in the case of a child with respect to whom the permanency plan is placement with a relative and receipt of relative guardianship assistance payments.

Requires states to check any child abuse and neglect registry maintained by other states in which a relative guardian has resided in the preceding five years before such an individual may be approved for placement of a child.

(Sec. 202) Directs the Secretary to establish up to 10 two-year demonstration projects to determine the extent to which flexibility in the application of certain licensing standards to foster family homes of immediate relative foster parents results in improved well-being and permanency outcomes for children in foster care.

(Sec. 203) Amends SSA title IV part B (Child and Family Services) to authorize the Assistant Secretary for Children and Families of the Department of Health and Human Services to make grants to eligible entities for the federal share (50%) of the cost of carrying out kinship navigator programs that help connect kinship caregivers with the services and assistance required to meet the needs of the children they are raising and their own needs.

Makes appropriations for such grants for FY2009-FY2013.

(Sec. 204) Amends SSA title IV part D (Child Support and Establishment of Paternity) to authorize comparisons and disclosures to state agencies of information in the Federal Parent Locator Service for child welfare, foster care, and adoption assistance program purposes.

Title III: Tribal Foster Care and Adoption Access - (Sec. 301) Amends SSA title IV part E to allow an Indian tribe, tribal organization, or tribal consortium, if specified requirements are met, to receive direct federal funds for foster care and adoption services for Indian children it provides. Prescribes requirements for determination of the federal medical assistance percentage (FMAP) for calculating such payments.

Authorizes an Indian tribe, tribal organization, or tribal consortium to receive a portion of a state plan allotment as part of an agreement to operate the John H. Chafee Foster Care Independence Program.

(Sec. 302) Directs the Secretary to make grants to states that successfully collaborate with and support tribes to improve permanency outcomes for Indian children.

(Sec. 303) Directs the Secretary to establish a National Child Welfare Resource Center for Tribes.

Title IV: Support for Older Children in Foster Care and Other Provisions - (Sec. 401) Amends SSA title IV part E to give states the option of covering certain children in foster care, and certain children in an adoptive or guardianship placement, after attaining age 18.

(Sec. 402) Requires a state agency caseworker and appropriate other representatives of a child aging out of foster care to assist the child in developing a transition plan personalized at the child's direction, which includes specific options on housing, health insurance, education, local opportunities for mentors and continuing support services, as well as work force supports and employment services.

(Sec. 403) Requires case plans under SSA title B or E to include a plan for ensuring the educational stability of the child while in foster care.

Title V: Revenue Provisions - (Sec. 501) Amends the Internal Revenue Code to: (1) require the children in adoption to be unmarried and younger than the taxpayer claiming a personal exemption for a dependent; and (2) restrict qualifying child tax benefits to the child's parent, or where no parent claims a qualifying child, to another taxpayer, but only if the other taxpayer's adjusted gross income (AGI) is higher than the highest AGI of any of the child's parents.

(Sec. 502) Provides for the collection of unemployment compensation debts resulting from fraud.

(Sec. 503) Authorizes the Secretary of the Treasury to invest U.S. operating cash in repurchase agreements with acceptable parties.