Oregon Revised Statutes Education and Culture § 328.213

(1) When authorized by a majority of the electors of the district, the board of a common or union high school district may contract a district debt for an amount which together with outstanding bonded indebtedness shall not exceed the bonding limit of the district as provided by ORS 328.245, for the purposes specified in ORS 328.205 and issue negotiable interest-bearing warrants of the district, evidencing such debt, and fix the time of payment of the warrants. Such warrants shall be considered a type of bond.

(2) The school district, not more often than once a year, may levy a tax on the taxable property of the district to pay the warrant interest or principal when due. The taxes shall be collected in the same manner as other school taxes. These warrants shall be sold, and the principal and interest provided for and paid when due in the manner provided by law for bonds issued under this chapter.