24 Pa. Stat. § 585.1
The Board of Public Education in school districts of the first class A shall levy annually, on or after the second Monday of November and before the first Monday of December following, a tax of three and one-fourth mills on each dollar of the total assessment of all real property assessed and certified for taxation in said district.
If such tax, together with other real estate taxes for school purposes, shall aggregate more than eleven and three-fourths mills on each dollar of the total assessment of all real property assessed and certified for taxation in said district, then such tax shall not be levied unless the electors of the district consent thereto at an election to be held at the place and time of any general, municipal, special, or primary election, and under the same regulations as provided by law for the holding of municipal elections at such election. The election officers shall receive ballots from the electors which shall be prepared in the manner prescribed by the Pennsylvania Election Code. If a majority of those voting on the question vote in favor of the increase, the school district may levy such tax annually thereafter.
24 P.S. § 585.1