It's a federal law. Your state may have a similar law as well.
I used to think the Supreme Court would throw out the "new" version of this law, but I'm not so sure about that any more.
18 USC Sec. 921
(a) As used in this chapter -
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(25) The term ''school zone'' means -
(A) in, or on the grounds of, a public, parochial or private school; or
(B) within a distance of 1,000 feet from the grounds of a public, parochial or private school.
(26) The term ''school'' means a school which provides elementary or secondary education, as determined under State law.
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18 USC Sec. 922
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(q)
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(2)(A) It shall be unlawful for any individual knowingly to possess a firearm that has moved in or that otherwise affects interstate or foreign commerce at a place that the individual knows, or has reasonable cause to believe, is a school zone.
(B) Subparagraph (A) does not apply to the possession of a firearm -
(i) on private property not part of school grounds;
(ii) if the individual possessing the firearm is licensed to do so by the State in which the school zone is located or a political subdivision of the State, and the law of the State or political subdivision requires that, before an individual obtains such a license, the law enforcement authorities of the State or political subdivision verify that the individual is qualified under law to receive the license;
(iii) that is -
(I) not loaded; and
(II) in a locked container, or a locked firearms rack that is on a motor vehicle;
(iv) by an individual for use in a program approved by a school in the school zone;
(v) by an individual in accordance with a contract entered into between a school in the school zone and the individual or an employer of the individual;
(vi) by a law enforcement officer acting in his or her official capacity; or
(vii) that is unloaded and is possessed by an individual while traversing school premises for the purpose of gaining access to public or private lands open to hunting, if the entry on school premises is authorized by school authorities.
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