§ 265.06 Unlawful possession of a weapon upon school grounds.
  It  shall  be  unlawful  for  any  person  age  sixteen  or older to
knowingly possess any  air-gun,  spring-gun  or  other  instrument  or
weapon  in  which the propelling force is a spring, air, piston or CO2
cartridge in or upon a  building  or  grounds,  used  for  educational
purposes,  of  any  school, college or university, without the written
authorization of such educational institution. Unlawful possession  of
a weapon upon school grounds is a violation.
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(For verification consult Official Text at Senate Gopher site.)