It is the policy of this State that all powers granted, either expressly or by necessary implication, by this Act, other Illinois statute, or the Illinois Constitution to any public school district may be exercised by those public school districts notwithstanding effects on competition. It is the intention of the General Assembly that the “State action exemption” to the application of federal antitrust statutes be fully available to all public school districts to the extent their activities are authorized by law as stated herein.